54 STANDARD METHODS JOURNAL Changes m New Edition of Standard Methods Of Milk Analysis* of MILK TECHNOLOG Y The forthcoming seventh edition of The only incubators approved are the water jacketed and anhydric laboratory types with Standard Methods of Milk Analysis (pub low temperature heating units operating at lished by the American Public Hea_lth temperatures only slightly in excess of 3? 0 C., Volume 2 March, 1939 Number 2 Association) will carry the new title and incubator rooms of proper constructiOn. "Standard Methods for the Examination Specifications for glassware are drawn in of Dairy Products." The ice cream sec greater detail than formerly. tion will be further developed by the More accurate methods are given for rinse Editorials work of the Joint Committee on Standard tests from glass and paper bottles. Tbe opinimzs and ideas expt·essed in papers and editorials are those of the respective authot·s. Methods for the Examination of Frozen The direct miscroscopic test is described in The expt·essio~s of the As.rociation are completely recorded in its transactio111. Desserts as approved by the Laboratory greater detail, particularly for the examinatioll, of pasteurized milk. All agar plates must be and the Food and Nutrition Sections of checked frequently enough to detect the pres the American Public Health Association. ence of excessive numbers of bacteria in milti Order Out of Chaos The most important changes in the new and cream where they do not grow on the plates. Only in this way can excessive num. The increasing public-health mindedness of the people has been finding at least edition are as follows: hers of bacteria be detected. one avenue of expression through the enactment of more effective programs for the The bacteriological methods in the first fiv_e sections cover samples, agar plate counts, dr The methylene blue thiocyanate tablets are sanitary production, processing, and distribution of milk and other dairy products. rect microscopic counts, methylene blue reduc accepted as standard. As one community after another inaugurated such control, standards for product and tion technic, and sediment tests. The four No reference is made to the resazurin tes · process were established which seemed adequate for the local conditions. Milk con following sections describe methods for the because further study must be made before the trol islands, so to speak, came into existence in scatterecllocalities all over the country. isolation and identification of coliform bac results are accepted as significant. teria, hemolytic streptococci, tubercle bacilli, The continuation of this sort of development has led to an increasing heterogeneity Reference is made tQ the modified form o£ in standards of product, requirements for production, and specifications for processing. and undulant fever organisms, respectively. the methylene blue··-reduction technic no'\\1 Section 10 includes ice cream methods, and officially approved in England. Sometimes, those of neighboring communities are contradictory, frequently they are Section 11 the butter methods. The text of The description of the sediment technic has inconsistent, and usually they are confusing in their varietY.. and exaggerated individu the bacteriological section has been rewritten, ality. The situation is even more confusing where the local requirements are not and a subject index prepared. been improved. Beginning July 1, 1939, standard agar me- Brilliant green lactose bile broth, sodium printed, or even if available, are interpreted by the unpredictable impulses of the dium is to have the following composition: formate ricinoleate lrtoth, violet red bile ~Sa,r; local enforcement officer. Bacto-Tryptone ...... 5 gr. and sodium desoxycholate agar are approved Compliance with the local requirements m').y be a needlessly costly undertaking. Bacto-meat extr...... 3 gr. for detecting coliform bacteria in dairy proo In the case of milk production on a milk shed covered by conflicting regulations, the Glucose ------······ 1 gr. ucts. farmer may find himself in the predicament of the fabled chameleon (a lizard which Skim milk ...... 10 cc. Methods for plating on blood agar and the (Where dilutions are greater than 1 : 10) use of Burri agar slants are described fo~ de changes its color to match its environment) which got on a Scotch plaid. It is even Agar ...... 15 gr. tecting pathogenic, usually hemolytic sp:ep more expensive for an equipment manufacturer to provide special, non-standard types Reaction ...... pH 6.6 to 7.0 tococci. References are given to methods of • of machinery in a territory where aggressive individualism is nonconforming, expres Preferred reaction ...... 7 .0 identifying species of streptococci by cultur.1l sive, and authoritative. While incubation at 37° C. (not 37.5° C) and serological procedures. Also tentative In an effort to alleviate some of these conditions, the International Association of is to be continued until laboratories doing methods are included for the identification of milk work are more generally equipped with tubercle bacilli and Brucella organisms in milk Milk Dealers organized its Committee on Simplified Pra~tice to help in securing agree approved incubators, the variation in tempera and cream. ment within the organization on uniform dimensions and certain standards for equip ture permitted was changed to 35° - 37° C. Directions are given for making yeast and ment and appurtenances. Secretary Hibben of the International Association of Ice rather than 35.5° - 37.5° C. as at present. mold counts on butter, and bioassays of vita· Cream Manufacturers has pointed out (1) the industrial hardship of arbitrary and Agar plates must be counted under con- minD milk. conflicting regulations, and urged the adoption of some procedure that would make stant illumination. The Quebec Colony It is expected that the new (Seventh) edi· Counter is recommended. equipment available that would be approved by all health officers. He stared that tion will be printed early in 1939. some health officials refuse to approve or condemn a piece of equipment until after it -.Summarized from Amer. J. Pub. Health 28 (12) J. H. SHRADER. ~as been installed. Some suddenly condemn a piece that has been in approved opera 1447 (1938). tion for years. He proposed that a joint committee of the ice cream manufacturers, the _suppli·es association, and the milk sanitarians set up a program for approval of equipment at its source of manufacture so that its stamp of approval would be ac ceptable to the different city, county, and state health departments. 56 EDITORIALS JOURNAL OF MILK TECHNOLOGY 57
The late President Calvert of the Dairy Industries Supply Association urged the Connecticut Association of Dairy and Milk Inspectors International Association of Milk Sanitarians (2) "to join with us in an attempt to set up some forum where there will be an exchange of opinion on the details of It is with great pleasure that we welcome the Connecticut Association of Dairy constru_ction and operation of dairy equipment so as to avoid the helter skelter, hit and Milk Inspectors into the growing family of dairy associations that are affilia~d an_d miss method _that now prevails." His association organized a Technical Com with the International Association of Milk Sanitarians through the Jottrnal of Mtlk mittee through whiCh they sought to establish cooperation in solving this type of their TechnoLogy. This influential group of_ eastern _milk inspecto~s took_ action at their problems. annual meeting on January lOth to destgnate thts Journal as 1ts offiCial organ. The To implement these reasonable presentations, the Committee on Sanitary Pro field of dairy technology and sup_ervision (both official and in~ustri~l) is broadeni?-g cedure was appointed last year by President Tolland of the International Association ,wd becoming increasingly techmcal. Every person engaged 10 th1s work needs In of Milk_~anitaria~s to co?perate with . the industry in a more general ptograrri of spiration as well as information f~om _ other workers. ~e ar~ sure that our new , standardizmg details of milk plant equipment. The first report of the work of this 1ssociates will make valuable contnbutions to knowledge m th1s ~eld, and that the collaboratio~ (3) ~howed that it was possible to secure an agreement on the design of service rendered by the JOURNAL OF MILK TECHNOLOGY w1ll be strengthened recessless p1pe unwns, tees and crosses, bends, and union nuts for connecting ther and improved. · m~meters to vats and sanitary pipe lines, that would meet all health department regu J. H. S. latiOns. This representative and highly qualified committee held that it could "ac cept" a pi·ece of equipment as being of the best possible design in the light of current Bang's Disease Eradication knowledge, but that this action did not assume that these designs were permanent. A_n example of the effect of this policy of acceptance of outstanding designs on the The plan for indemnifying owners fo~ animals which react to the agglu_ti~ation stimulus to make further improvement was the immediate invention of an ingenious blood test for Bang's disease becomes effective under federal and state supervtswn on a?d inexpensive union nut for att~c~i~g. indic_atin~ ~herm?meters to vats and pipe May 1, 1939. Both the tube an? plate te~ts are ~eing used in testing cattle und~r hoes. The success attendant on th1s Imt1al actwn IS mduove for these collaborative this project. The general operative plan rs practically th~ same as that already 10 committees to extend their studies to other types of ·equipment. · force for the eradication of tuberculosis and paratuberculosis, whereby the owner, the The policy of the Committee on Sanitary Procedure has been to review only those state, and the federal government respectively assume one-third of the differen~e be designs which are submitted to it by the trade. It would .seem that in the light of tween the appraised value and the salvage value at ~laughter of ~ondemned ammals. the above developments such conservatism is not warranted. This committee is com Last fall all breeding cattle over 6 months of age 10 300 counties of 22 states had posed of men from all parts of the country and from both the official and industrial{ been tested. In 4 states, more than half of the bree9ing cattle are under supervision aspects of quality and regulatory control, interested in and thoroughly conversant· in the federal-state campaign which has been in force since 1934. During the month with all the demands on dairy equipment. They know the kindJof ·service that is of December 1938, the blood agglutination -tests were completed on 587,529 cattle, required of equipment- the needs of operations, the type of job''that should be done, of which 17,302 were found to be reactors. At that time, there were a total of t?~ :v_ants of the health o~cer. !hey also know equipment, its ·limitations a~d pos 1,202,195 herds, and 10,280,003 cattle under supervision, and an additiona~ 1,015,~44 sibt!Itles. They are strategiCally situated to set up des1gn and performance objectives cattle on the waiting list. The results of the program have shown that m the high for manufacturers of equipment to attain. The latter can do a more inelligent job majority of herds, Bang's disease yields to systematic control 'efforts. :vhen they understand clearly what is wanted. The old adage ~t a prq_blem define . ,1.. J. H. S. 1s already half solved is true in this instance also. So it is hoped that this Committee will take the initiative, and announce sanitar~ and performance principles that should be incorporated in the design of every kind Standard Methods for the Examinafic:>n of Dairy Products of equipment that is used in dairies. It should not set up specifications. These should be left to individual initiative and competitive effort. We do not want regi The American Public Health Association announces that the new 7th edition of Standard mentation. Its function would be twofold, namely, to announce desirable principles Methods fur the Examination of Dairy Products should be available for purchase early in April. that should be incorporated in design, and to accept and publicize those designs which On July 1, 1939, we are to begin the use of the new standard agar medium in which the pep it considers to be satisfactory. There seems to be no sound reason why the combined tone has been changed frvm a meat-digest peptone to a casein-digest peptone. A small amount of glucose is to be added, and where dilutions are greater than 1 : 10, there is to be added 1 intelligence of this committee, collaborating with committees from the trade organi percent of skim milk or equivalent amount of spray process powder. "The purpose in adding zations, should not chart the course, so to speak, of desirable development, and save the milk to the higher dilutions is t.:J eliminate the type of discrepancy in count that is produced the industry from futile journeyings and costly groundings. Particularly valuaBle by the presence of milk solids in plates made by the direct addition of milk or in dilutions as would be its service in facilitating the production of equipment of the kind that the low as 1 : 10". Laboratorians are cautioned to watch carefully their incubation temperatures to industry and the health officer really needs. make sure that they do not exceed the specified standard temperature of 37° C. (98.6° F.) . The several phosphatase tests will be included in an appendix, giving the latest directions 1. Some sanitary problems in the ice oeam industry, by R. C. Hibben. J. Milk Techno!. 1 for the 'various types of the more promising technics. No comparisons have yet been made (3) 43 (1938). concerning them, and therefore not any of them s111)uld be regarded as standard. . 2. Standardiz,ltion of rulings on equipment and supplies, by H . S. Calvert. Ibid. 1 (2) 10 The new edition of this valuable book cootains so many improvements and suggestions (1938) . concerning the better use of labo.:>ratory m~thods that it should be in every laboratory engaged 3. Report of the Committee on Milk Plant Equipment and Committee on Sanitary Procedure, in milk work. by W. D. Tiedeman, Chairman. Ibid. 1 (7) 4 (1938). J. H. S. J. H. S. li ible by 1936 the percentage is important because of the intimate re wJd ci:!n ~a s'3 percent for communities lationship between dairy farm water sup h·• oOO population and over, and to plies and the process of milk production. 0 Engineering Problems in Milk Sanitation* of ~ ' 75 percent for communities of Contaminated water supplies would mean n :~~J pqp.ulation and over. Such accept- that the slightest relaxation or accident in Leslie C. Frank, 1·0 by the people of this country of the the bactericidal treatment of milk uten nee · f h · bl" · 'lk sanitation adv1ce o t e1r pu K sils and ·equipment which had been U. S. P~tblic Health Sertlice, Washington, D. C. ~:.lith authorities should be profoundly w~shed in the dairy farm water supplies m1ght produce disaster. Local milk in stimulating. · . . . ltztrodt~ction.-Until fairly recently san gr?wn that the pasteurization of all Now the use of the pasteunzatwn spectors have paid insufficient attention lt~ry en,tpneers have not considered that mtlk supplies, an essentially eng· ma~et t once poses problems of the de- to farm water supplies. mtlk samtation was a problem with which - . tnee.t;mn roce Ss a f · · Pro bl em, 1s a VItal necessity Th' . o p. and operation o pasteunzatton Dairy farm exC1'eta disposal. In most · IS l S be they s~ould much concern themselves. cause we h ave learned that no oth . s•gn. ment and it is at this point that the cases, water carriage of exaeta is not re ~onclus1ve evid~nce of this may be seen . f er meas I'() Uip ' . · ure an d' m. act, no combination of ot!h . ~·isdom of adding samtary engmeers to sorted to on dairy farms. Instead sani ~n the past curncula of sanitary engineer measures, g~ves adequate protection. er h milk sanitation staff becomes sharply tary privies of the pit type are widely mg cour~es. Practically none of the grad Tuberculm testing and other t t ~ e arent. This has become parti~ularly used, and while such privies are relatively ~ate santtary engineers i? the n.eld today the. health of animals nearly, thou e~s of t p~ since the advent of automatiC pas simple their design and construction are a study of mtlk samtation in mc~uded entirely, remove the bovine tubelf:w within the province of the sanitary en thetr undergraduate courses. n~t l~~rizatio n systems, as will be made cle.ar menace and reduce the danger from ~sts later in this paper when we cot;ne to dis gineer. In some cases, too, farms de Indeed,. milk sanitation has in the past !ant fev~r, but these measures do no~ u cuss the pr blems of thermo?tat1c c_ontrol, sire to use a water carriage system of ex ~ee~ cons1dered to be a problem for veter tect agal.nst streptococcic udder infecti~~o milk-flow stops, valve des1gn, atr and creta disposal, and in thes·e cases the t ~anans, bacteriologists, and epidemiolo nor. agamst other milk-borne diseas s, foam heater design, regenerator design, sanitary engineer should be called upon to gists ~ather than for engineers. Milk is a h' h e or g. nlsms w lC may enter the milk after .md others. give advice. an antmal product and its sanitation is re 1t has been dra:vn from the udder. However, the function of the sani~ary Pasteurization pla11t design. In pas la~ed to t.he health of animals. Therefore Health examinations of employee engineer is not limited to the immed1ate teurization plant design we have the m~lk sanrtation is a problem for veterin ... s aro va lblbua e . ut f at! to eltmmate comP.letel problem of pasteurization.- His work problems '?f adequate light and ventila ana~s. It is advisable to make bacteri the. typhol_d carrier, and are relabiv: really begins at the producmg farm. In tion, proper construction of floors, walls, olo~tC~l an.alyses of milk. Therefore milk f~ver ly. m. the contamtn. milk control and processing, the more and ceilings, proper drainage, proper lay sa~1tat1~n 1s a problem for bacteriologists. meffectr~e P.~ey,ooting atwn of mtlk wtth fhe organisms of se bic important items to which t~e sanitary en out to separate the milk receiving and Ep1de.mtCs occur as a result of unsafe milk sore throat, scarlet fever and d'ph•h P. gineer should devote attentwn are as fol- uten.sil .cleaning processes from the p~s suppltes. Therefore milk sanitation is a 1 Th 1 . ' " ellla. teunzatwn and subsequent operations, so problem for epidemiologists. Thus has e c eanmg ~nd sterilization of contain- lows: as to avoid cross-contamination, and the run the philosophy of milk control here ers .and ';Itenstls offef valuable proted ion Dair[Y bam and milk hottse design. One agamst-disease orgaetsms which may reach proper design and installation of milk ~of~re and such was the status of milk san of . e first items with which he should rece!vin_g, filtrat~on or clarification, pas ltatwn until twenty years ago and even t~e .mllk ~rom equipment, but cannot conaern himself is the design of the dairy elunm~te d1sease organisms which enter teunzatlon, coolmg, and bottling equip late.r. At t~at time only one or two state barn and milk house, the drafting of the mtl~ before it comes in contact with ment. sa~1tary engmeering divisions were inter plans wh ich will insure that t~ere . is estmg the':lselves in milk control. In fact, the eq~up':lent, nor p~event subsequent adequate space to prevent contammatwn The engineering divisions of several contammatton of the mtlk through spittle due to overcrowding, adequate light to state boards of health have devoted some the states m. genera.! were doing little, if droplets, dust, or fi·ies. ' any, real mtlk samtation work. Actual insure cleanliness morale, adequate ven attention to the drafting of plans for enforcement of milk regulations was then . In short, pastettrization is the only .'fltlb· tilation to prevent the absorption of odors pasteurization plants. Figure 1 shows a and still is, primarily a function of ci~ Ire. healtk measure which, if properly ap. and flavors and the drip from condensa plant developed by the sanitary engineer ing division of one of the southern states, health d~partments, but not a single city f!lted,. will tUf:equately protect against all tion on the ceiling, proper construction of floors and walls to promote easy cleaning, namely, North Carolina. In that state, ~t that ttm:e em~loyed a sanitary engineer mf~cttotts mt!k-bome disease organi.smJ m connectwn w1th milk sanitation work. whtch '?zay. have entered the milk prior o and proper arrangement to facilitate the the division offers its services to milk dis pastettrtzatton. Obviously the milk must required sequence of operations. tributors who are contemplating the con As ti~e has gone on, however, it has struction or reconstruction of a plant. bec?m~ 1~creasingly apparent that milk be protected against recontamination. . Dairy farm water s~tpplies. The next santt~tlo~ IS not exclusively a problem for This growing conviction of the all-im 1tem which should receive the attention This calls attention to another and even vete~manans, bacteriologists, and epidemi portance of pasteurization has been re of the sanitary engineer is the design and more recent development. In the 1939 ologists. The conviction has steadily fi~cted in an .increase in the percentage of c~nstruction of dairy farm water supplies. edition of the Public Health Service Milk mtlk pasteunzed. Thus while at the be Stx and one-half pages of the Public Code there will appear the requirement *~resented at 1939 Annual Meeting American So- gi?ning .of the century the percentage of Health Service Milk Code are now de that plans for all dairies and milk plants Ciety of Civil Engineers. ' mtlk whKh was pasteurized in this country voted to this item alone. The subject which are hereafter constructed, recon- JOURNAL OF MILK lECHNOLOGY \H
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FIGURE 1 FIGURE 1 ucy-ollt of Milk Ptrsteuriz Not~s: 1 floors shall be of conCI·ete, tile or other rmpet·vrous material and shall slope to health department. This requirem . ll.ll aeriaL pollution, and faulty drinking In either case the problem arises that parallel the similar requirement lent Will if leakage develops in the metal separat trapped drains at the rate of abortt ¥.f" per . t' . ong ex fountains . foot. Drabu should be located at the ends of IS mg m many states that plans fo • PasJetlrization plant excreta and waste ing the raw from the pasteurized milk, rounded gutters running along the base of the and sewage structures must be . Water or separating the milk from the heat walls. Floors should slope from the center of . al This problem does not often a room toward these gutters. Tliis method of by the state health department. It is ,/Jspos ·the attention of a sanitary en- transfer medium, and simultaneously the engage · · f · t raw milk is under higher pressure than floor drainage will insure a dry floor in the able to believe that in the futur . gineer, as in the maJonty o Idns ~nhces cent~r of a room, which is the most travelled be . e It Wi]( the pasteurized milk or the circulating portton. a routme matter for sanitary en . ~tet~nizat ion plants are connecte wit a bl'c sewer. However, some plants are medium, then the raw milk may contam . 2 Wails and ceilings should be finished with ing divisions of state boards of h g; ~er. ~at~ CI outside ~he public sew_er districts inate the pasteurized milk. For example, trle or hard portland cement plaster. be required to pass upon all plea t to such higher raw milk pressures are often (Valuable information on concrete and t · · ans for d in these mstances speCial sewage pas eunzatiOn plant construction encountered because of the practice of cement plaster may be obtained from the Port construction. or re. Jn atment plants must be designed. This lantj Cement Association, 33 West Grat1d Ave. ~ ay require experience beyond the ~r placing the milk pump upstream from Chrcago, Ill.) ' Pasteurization plant water sttppN the raw side of the regenerator. · . e.r. At dinary problems rel~ted ~o excreta dis 3 All oP_mings into the outer ait· shall be fi rs t t h ough t It might be as~umed th The solution, obviously, is to develop screened wrth 16-mesh wire sct·eening to pre- posal a.s. special consideratiOn ~ust often 1/ent the entrance of flies. Screen doors must nearly all pasteurization plants use "' bl~ be given to the treatment of dairy wastes design, installation, and operation speci . I' I . 'IO U IC open outward. wa t er :mpp .'es exc usi~ely and the(efore other than excreta. In the past the so fications to insure that the pasteurized 4 All doors must be self-clositzg. do ~ot requ~re the ~peCial attention of the lution of this problem has often been milk side of the regenerator is under higher pressure than the raw milk side 5 .Powerful ftms should be itlstalled at the sa~Itary engmeer, smce public water unsatisfactory both because of the com outsrde entt·a1zces to the receiving room wash whenever there is any raw milk in the ph~s ~r~ presumably already within position of dairy wastes and because of boom and loading vestibule. These fans ~hould their ext&me variability in amount and regenerator, including not only the rout . ~ o pera_ted so as to prevent the entrattce of JUn~d!ctlon. However, a numbev of ine flow period but also at the beginning fires whtle these entt·ances are being used. teunzation plants are located kind during a single 24-hour period. For of the day's run and during interruption 6 Sepa~ate equipment must be pt·ot•ided for limits and have their own example, within a period of a few hours, the handlrng of sout· milk pt·oducts. the waste may vary from buttermilk vat periods, when the pressure picture may water supplies. In addition a be quite different. Such specifications . 7 All milk piping must be at least Jill' in drainage of low pH to the relatively srze. 12 nu~ber of plants make dual 'u;e of have been worked out in detail and des an mdependent and a public wate c:IUstic drainage from a bottle washing . 8 Equipment. must conform to the specifica 11 cribed in ·Public Health Reports (1). • ply, and frequently have them eros's:= co 111 machine. tro.ns of tke Unrted States Public Health Service The s ~lution involves not only the Mrlk Ordrnatzce and Cod'e. nected .. Therefore eac~ sl!ch plant . Design.. and operation of regenerators. be st_udied by th~ sanitary engineer to de. proper placing in the flow line of milk ? Refrigeration equipmem should be selected 1 We have here a problem which involves befot·e cotutruction of cold storage and com termu:e whether such independent water pumps and heat transfer medium pumps pressor rooms is begun. an engineering study of relative pressures so as to take proper advantage of the supphe_s as are used · are safe, and whether in various parts of a heat exchange system. 10 Joints between floor and wall should be there. IS any cross-connection with the differential between suction and discharge t'ounded to a radius of about one inch. A regenerator, as understood by the milk publiC water supply~ pressures but also- proper elevations for ! 1 Floot·s shou(d be reinforced with metal in !l)JStry, is simply a heat exchanger which the free milk levels, upstream from and g~rd P!ates at pomts of hardest service, espe . Plumb~ng. Pastcttri za~ion plant plumb IS designed to permit the incoming cold downstream from the regenerator so that craliY, m the receiving and cold storage t·ooms mg. cons~Itutes another Important raw milk to recapture some of the heat proper relative pressures may obtain dur and 112 the loading vestibule. engmeenng problem. In 1935 W. "'"'"·• from the outflowing hot pasteurized milk. 12 The milk pipe line from the receivin Johnso_n read an. excellent papen on The regenerator may be either of the ing sht.Itdo~ns. In addition, in certain room m_u;t be brought through the floor of th~ plumbmg hazards m pasteurization plan ts "tube within a tube" type with the heat designs it is necessary that hot water, pas~eurtz112g_ room in such a way that floor chlorine solution, or previously pasteur 4ra112age wrll n~t drip down through the open before the Engineering Section ofi the exchange taking place between the milk rng and contam112a~e equipment in the receiving American Public Health Association. He in the inside tube and the milk between ized milk must, at the beginning of the ~oom below. A prece of 4" cast-ir011 pipe cast described. the result~ o~ a plumbing sur· the inside and the outside tubes, the latter day's run, be introduced into the pas 112 the floo;. and projecting about 12" above yey of s!x pasteunzat10n plants loc;:ared flowing counter-current to the former; or the pasteurrzmg room floor is a good cond'Uit. teurized milk side of the regenerator be 1n the _City of St. Louis. He reported the. regenerator may be of the plate type, 13 Tjle clarifier. must be connected to the fore raw milk is admitted to the raw milk P_asteurrzers by sanrtary milk piping and connec the fi?dmg _of 210 separate plumbing de· wh1ch consists of a series of adjacent side. Otherwise the raw milk side may tror.s. fects mvolvmg 28 different kinds of milk plates separated by gaskets and with a at this time be above atmospheric pres system so designed that the cold raw plant e9uipment and including direut pipe fl~w sur-e and the pasteurized milk side at at co~mect10ns between potable water sup· m1lk and the hot pasteurized milk flow mospheric pressure. Figure 2 shows an plies and sewage or contaminated water in ~lte;~ate layers between the plates. structed, or extensively altered shall be supplies, potab~e water inlets submenged Agam e1ther of these two constructions illustrative flow chart designed to insure submitted to the health officer for ap ~o as to permit back siphonage during may be employed but so arranged that that the relative pressures in th ~ regen proval, and the fu~ther requirement that mtervals of negative head, sewer lines the pasteurized milk transfers its heat to erator will always be such as to prevent m the case of mtlk plants signed ap !orated above pasteurizers or other milk a circulating water medium which in turn contamination of the pasteurized milk by proval shall be obtained from the state processing equipment, instances of 1poten- warms the raw milk. the raw milk. MILK ENGINEERING jOURNAL OF MILK TECHNOLOGY 65 A . d indicating thermometer bulbs might leak out through the outlet valve into the r-->---t--t=~To Boffler ~ and frequently was higher than the pasteurized milk line before it had been I k temperature of the milk in other parts of completely pasteurized. It was also dis ~ B- rree md;.. !ere! the holder, e. g., the zone between the covered that raw milk might leak through face of the outlet valve. and. the main body the inlet valve and recontaminate the milk /teoter f the milk. The m1lk tn such outlet in the vat while it was being pasteurized. ~ones was frequently found to be 10° F. So the Public Health Service inserted a more below the temperature of the requirement in its recommended Milk R~~neraf-or ~ain body of the m!lk. As a r~sult of Code that all inlet and outlet valves must this .finding, the requtrement was mserte~ be of the leak-protector type, that is, so ·n the milk code recommended by the designed as to divert to the outside, by /?awM/1/( ~ ~ublic Health Service that the design of means of leak grooves or otherwise, any Supp6' lQn/( the holder shall be such that simultan~ous leakage which attempted to pass the valve temperature differences. betwe_en. vanous face. Cooler points in the holder will be ltmtted to a Satisfactory types of valves were de ChecA- 1/a/Pe tolerance of not over 1 o F. Furthermore veloped both by the Public Health Ser all outlet valves are' required to be of the vice engineering staff and by the industry FIGURE 2 flush or close-coupled type, that is, so and are described on pages 88 to 97 of designed a~ to bring the face of the out the Public Health Service Milk Code. E.~·ample of Lttyortt to In.rm·e Proper Regenerator Pt·e.rsttres Notes:- let valve close enough to the. m~in body Figure 4 illustrates one type of leak-pro -~ ~- = Rau• Milk of the milk in the vat to eltmtnate the tector valve. - ~ ------ now requires that if cooling is begun in be rep~steurized and the ever-present the holder after the opening of the outlet temptatiOn on the part of the operator to valve, or is done entirely outside of the shirk the responsibility in order to sa holder, the recording thermometer charts tune.. I n t h ese cases It . has beeru co" ~ shall show not merely 30 minutes, but sidered fundamentally necessary, in. ~ 30 minutes plus the emptying time down 1 formulation of the Public Health Se,..,,1 to the }eve! of the recording thermometer MI'lk Co de, to surround all automatj·~~ bulb. pasteurizers with all necessary safeguar~ A1itomatic pasteurization systems. Auto to insure that the likelihood of eithe matic pasteurization is rapidly replacing temperature or holding time failure wilr manual pasteurization, particularly in the be reduced to the very minimum. larger plants. This trend, as might be Thermostatic control. Accordingly the expected, is introducing a whole series of first requirement which has been laid sanitary engineering problems. In the down in the Public Health Service Milk case of the relatively simple manually op Code is that all automatic systems mus erated vats, if the design requirements be provided with thermostatic control of previously described have been satisfied, the temperature of the milk entering the and if the thermometers show that the pasteurization temperature has been ap holder. This requirement has fu.rthcr plied for the full holding time, the op been expanded, for purposes of conven. erator can open the outlet valve and dis ience, and in order to avoid what might charge the milk with the assurance that be termed "hay-wire" pasteurization, to it has been properly pasteurized. If the include any system in which the milk is recording thermometer does not show brought to the pasteurization temperature both the required temperature and the before it enters the holder. Obvious!)• required holding time he can either in it would be possible to have an operator crease the temperature or the holding continuously present at a temperature con. time, or both, before opening the outlet trol valve as a substitute ·for thermostatic valve. The point is that the milk is not control, but whilt( this might give good discharged to the cooler and bottler until results most of the time, it is obvious the operator deliberately opens the outlet that the slightest lapse in attention would valve. It is his duty and he always has result in the passing of unsafe milk the opportunity to assure himself that the A11tomatic milk1Jow-stops. Since even process has been properly applied before the best thermostatic control occasionally he opens the valve. fails, it was highly advisable to ineludr In the cas·e of automatic pasteurization, an additional safeguard which would however, both admission to and discharge function at such times and serv·e as an from the holder are automatic and unless extra factor of safety. The best such otherwise prevented will take place even safeguard is a device which will auto· if the milk has not been brottght to the matically hair the flow of milk beyond pro per tem peratttre or held at that tem the holder If the thermostat fails or i( perat!lre for the pro per time. Further any temperature drop occurs in the more, since the holding time is automatic holder. It was soon found that such a ally controlled, any temperature failure "milk-flow-stop" could take either of two in the holder would require emergency forms: manipulation of the automatic time con ( 1) An automatic milk pump stop trol, or diversion of the entire supply which would automatically stop the milk back to the heater until the t·emperature pump motors whenever the milk tet?p~ra· failure had been corrected. This, in the ture dropped below the pasteunzat!On FIGURE 6 case of batch type holders, would be ex temperature and automatically restart the Flow-diversio11 valt'e tremely hazardous because of the quan motors whenever the required milk tem· tity of milk which would be required to perature was again reached, or JOURNAL OF MILK TECHNOLOGY 70 MILK ENGINEERING 71 (2) An automatic milk-flow diversion remain at or above the pasteurization n ~ ~' device which would automatically divert temperature, it is necessary that a milk ~ ~ ~ ~ ~'\- ~t~ the milk away from all downstream flow stop be located upstream from the ...... ~~ ~ ~ 'I> i ~ ~ points whenever its temperature dropped holder, as otherwise milk might enter "l: t tJ ~~ L. ~ ... ~ ~~ - ~ ~ ~'li below the required pasteurization tem the holder below the pasteurization tem ~ 1.. ~-~ ~ ~~l!: ~ .. ~ 't~~~ perature, and automatically reestablish perature, be raised to or above the pas ~ ~. ~~~ ~ ~ ~ <>~ ''~ ~ "t ~ ·"'~ ~ ~~\I., 'I h '{: forward flow when the milk again reached teurization temperature during the hold I( II> d "t~ \! ~~ Q; ~ ~ ~ ~ £~'\\ the required temperature. ing period by the supplementary heating ~ \ ~ Z' #4#k..- ~ ~~ ~ ~t·~ device, and thus pass the 'milk-flow stop bl -- -<- ---, ~ ~ ~ Figure 6 illustrates an automatic flow g ) ~ ~ ~" ~ -~'"~>\. " with impunity if it were lomted down ~~ IJ ~ stop of the diversion valve type. ! 0 ~~ I • T ~ -~ ~ ~ -~ The requirement that a milk-flow stop stream from the holder. ~ "~ ' Again, if the holder is so designed that ~t ~ q-~ be installed immediately brought into ~~ /~~\\~ focus two collateral problems, namely: some of the milk may drop significantly ~ (1) What should be included in the in temperature before the end of ·the specifications for "milk-flow stops"? and holding period it is considered necessary (2) Where should they be required to that a flow stop be locatttd downstream; be located? from the holder, as otherwise milk may; enter the holder at the pasteurization FIGURE 7 After careful study a set of specifica temperature, drop below it during the tions for milk-flow stops was inserted in Automatic Pasteurizatio11 System with Thermostatic Coutrol and Flow Dit,eniou Valve. holding period, and thus have passed the ( diagramatic elevation) the Public Health Service Milk Code. milk-flow stop with impunity if it were These include (a) the sealing of the located at the inlet to the holder and nob milk-flow stop setting so as to insure that at the outlet. any change in the setting will come to the attention of the health officer, (b) Finally, if the holder is so designed when the heating medium drops below the sion, but enough has been said to demon the prohibition of manual switches which that the milk in it may either rise in tem temperature required to keep the milk strate two important facts: perature or drop significantly in temp~a would permit cutting out a milk-pump throughout the holder at the required (1) Milk sanitation is a problem which stop, (c) the prohibition of any by-pass, ture before the end o£.the holding period, temperature. it is, of course, 'hecessary to require a now req_ttires and will in the fJJttlre in (d) required routine daily tests for cut Further study showed the necessity for creasingly req11ire the seriom attention of out ancf cut-in temperatures, (e) the re milk-flow stop both .upstream from and downstream from the holder. a number of special requirements for sanitary engineers. quirement that failure of the primary mo systems in which the milk-flow stop is It Figure 7 illustra•te~ a flow diagram for is rapidly becoming apparent to state tivating power will automatically stop or lo ~~d upstream from the holder, and boards of health that their sanitary en divert the flow, (f) the requirement of an automatic 30-mitmte pasteurizer of the multiple holder type, with a flow div.en otHer special requirements for systems in gineering divisions should be related to leak-protector features on all flow-diver which the milk-flow stop is located down the problem of milk sanitation. Informa sion valves, (g) the requirement that the sion valve located upstream from the holder. stream from the holder. To give the de tion collected by the Public Health Ser actuating bulb of the flow-diversion de tails of these special requirements would vice shows tnat in at least 25 states milk It at once becomes apparent that ~he vice shall be located immediately up uodesirably expand this paper. sanitation work is now being done by the stream from the valve, and (h) a limita above specifications are dependent .£or There are obviously also special re divisions or bureaus of sanitary engineer tion of thermometric lag, and routine their effectiveness upon a P.roper defini ing, whereas two decades ago only one tests required to determine its magnitude. quirements with reference to time control tion of "significant temperature dr~p". for automatic systems. These include re or two state sanitary engineering bureaus With reference to the location of the After careful consideration this term was quirements relative to the use of constant interested themselves in the problem. A milk-flow stop, it became apparent that defined in such manner as to allow a speed motors or limited maximum-speed similar tendency is beginning to appear in if the holder system is so designed that temperature drop of not more than 1!° F. motors on milk pumps and timing de some of our local health departments. the milK therein can neither increase nor when only automatically controlled holder vices, the prevention of inter-pocket flow, The total number of sanitary ·engineers significantly decrease in temperature be heaters are turned on during the belding the prevention of air or gas accumulation engaged in milk control in this country tween the time it leaves the heater and period, and of not more than 2Y2 o .F. in tubular or equivalent stream-flow hold is now: the end of the holding period, the milk even if all automatically controlled he!Cier ers, and,the checking of the holding time (a) By the state boards of health-1 7 flow stop may safely be located either heaters cease functioning at the beginning by means of dye tests, or otherwise, im full time and 75 part time, and ttpstream from or downstream from the of the holding period. Automatic:ally mediately after installation or after any holder. (b) By local boards of health-14 full controlled holder heaters are defined as replacement or alteration in design. time and 36 part time. If on the other hand the holder is pro heaters which are connected with an up vided with a supplementary heating d_e stream milk-flow stop in such manner as ~onclusion. Many details have neces This paper should not be understood vice intended to insure that all zones will to stop the flow of milk into the holder sanly been omitted in the above discus- to imply that only public health engineers MILK ENGINEERING 73 should be employed in milk sanitation. referred to in this paper, such as ·the sani That would be as unwise as to insist that tation of water supplies, excreta disposal, only veterinarians, or only bacteriologists, dairy wastes disposal, etc. Symposium on Frozen Desserts or only epidemiologists, or only dairying (2) Sanitary engineers should be ade graduates should be employed in this qttately trained to discharge their milk F. W. Fabian, Editor field. Nor should this paper be under sanitation functions. stood to imply that all milk sanitation Michigan State College, East Lansing, Michigan. It has been emphasized in this paper : work must necessarily be under the ad that the sanitary engineers of this country minis~rative direction of a sanitary en face a grave responsibility in connection The American Public Health Associ other associations working in~ this field, gineer. The capacity for administration with milk sanitation. As evidence of the ation considered the subject of frozen and many of the referees (committee does not reside solely in any one profes magnitude of this responsibility a survey desserts of sufficient and timely interest to members) and associate referees are ac sion. If a state board of health employs conducted by the Public Heal·th Service devote a symposium to it at the last annual tive in committee work on frozen desserts more than one individual in milk control, for the year 1936 developed the fact meeting at Kansas City, October, 1938. in other associations. The organization of the one who shows the best administra that in communities of more than 1,000 These papers are devot~d to bringing out the Joint Committee is as follows : tive capacity should be placed in admin population, over 5,000,000 gallons of the various aspects of this whole subject Friend Lee Mickle, Chairman. istrative charge, irrespective of whether milk per day, or over 1,800,000,000 gal with a view to familiarizing health officials he is engineer, veterinarian, bacteriologist, lons of milk per year are pasteurized. with the problems in the field, and there A. H . Robertson, Referee, Microbiolog epidemiologist, or dairy ·expert. To insure that no part of this ocean of by assisting them in coping with the situa ical Examination of Frozen Desserts. Nevertheless it seems inescapable, from milk may transmit disease is a problem tions encountered. We are indebted to the F. W . Fabian, Referee, Microbiological the facts presented in this paper, that of such magnitude that it is not •too officials of the American Public Health Examination of Ingredients. every state health department without much to ask that the future graduate AssoClatiOn for their kind permission to M. J. Prucha, Associate Referee, Micro exception, should employ at least one sanitary ·engineers who will engage in re lease the papers for publication here biological Examination of Flavors, sanitary engineer full-time on milk sani this work be properly trained for it. It with. Colors, and Extracts. tation work and, where possible, the milk is still true that 'most of the sanitary en In order to avoid any unnecessary dupli P. A. Downs, Associate Referee, Micro control work should be a function of the gineers who graduate today are without cation within the Association and with biological Examination of Condensed state sanitary engineering division. Ex the necessary specialized training and it other associations engaged in similar lines and Evaporated Milk. cept in the case of large cities which em is believed that every_jnstitution which of work, an explanation will be given of P. S. Prickett, Associate Referee, Micro ploy their own sanitary engineers, no prepares men for the'sanitary engineering the organization of the work for the study biological Examination of Dry Milk. pasteurization plant should be constructed field should ponder .the desirability of o'f frozen desserts. or reconstructed and no pasteurization including milk sanitation as one of the H. H. Hall, Associate Referee, Micro equipment should be installed or modi subjects of instruc-tion. JOINT COMMITTEE FOR ANALYZING biological Examination of Sugars, fied without ·the approval of the milk Those sanitary ·enill;!eers who have al FROZEN DESSERTS and Sweetening Agents. sanitation engineer. His services should ready graduated and who are now en Sanitarians and public health officials P. H. Tracy, Associate Referee, Micro be available to all city health departments gaged in or may in the future wish to have believed for some time that sufficient biological Examination of Fruits and in connection with the interpretation of undertake milk sanitation work, should information was available and that there Nuts. any item of sanitation which is of an en either attend post-graduate courses in milk was a need for a standardized procedure L. H: James, Associate Referee, Micro gineering character, and he should be sanitation or one or more of the milk fo r analyzing not only frozen desserts but biological Examination of Eggs and prepared to give the city health depart sanitation short courses or seminars which also the ingredients from which they were Egg Products. ments advisory assistance in connection are being conducted by various state made. These sentiments >yere crystallized James Gibbard, Referee, Microbio with the testing of holding time, thermo boards of health and the Public Healtll at a joint session of the Laboratory Sec logical Examination of Stabilizers. Service. metric l~g, the approval of indicating and tion an d the Food and Nutrition Section Associate Referees : P. S. Lucas, T. B. recording thermometers, milk-·flow stops, of the American Public Health Association Downey, A. C. Fay, A. G. Lochhead, regenerators, etc. In addition, the ser 1. Contamination of Pasteurized Milk by at the Sixty-Fifth Annual Meeting in New Improper Relative Pressures in Regener A. C. Dahlberg, A. S. Ambrose and vices of the sanitary engineer should be ators. Reprint 1921 from the Public Orleans in 1936. Action was taken to M. P. Horwood. (added later) . available on all other items previously Health Reports, April 1, 1938. establish a joint committee composed of members of these sections. This Joint J. H . Shrader, Referee, Chemical Anal Committee for Analyzing Frozen Desserts ysis of Frozen Desserts and Ingredi was placed under the supervision of and ents. was made responsible to the Coordinating C. D. Dahle, Associate Referee, Deter Committee on Standard Methods of the mination of Milk Solids in Sherbets. Laboratory Section, and is allocated to the W. H. Martin, Associate Referee, Use Committee on Research and Standards. of Modified Babcock Methods for .,£.,. ___._ __ The work has been integrated with that of Ice Cream. LOMMITTEE ON FROZEN DESSERTS H. H. Sommer, Associate Referee De and approved by the Joint termination of Acidity in F~ozen er~es, Desserts. mJttee, they will be mimeographed sent t? as many Iaboratori·es as ~d M .. E. Parker, Referee, Sediment Test for tnal and criticism. These pr i~O~iblt What Are Frozen Desserts? tog D. Pasteurization. In fruit, chocolate, and nut ice cream 3. 1.6 lbs. of food solids per gallon. c. 3 lbs. of wholesome egg yolk 1. All ice cream mix should he p<~s these substances also serve as the sourc~ 4. 5 percentum by weight of clean, containi~g not to exceed 55 per teurized at a temperature of not of the total food solids. mature, sound fruit or the juice cent mo1sture, or less than 150° F. for a period of (4) Eggs include the whole fresh egg; thereof, or the equivalent thereof, d. the equivalent of wholesome not less than 30 minutes, and w_hole frozen egg, or whole dried egg: and conforms in name to the egg yolk in any other form. promptly cooled to a temperature Smce the yolk is more directly respons~ fruit or the fruit juice used in its 5. With or without fruit or nuts. of at least 50° F. or lower, and ble for improved flavor, texture, and preparation. (See (8) under In making a parfait, the yolks held at this temperature until whipping quality of the mix, it is used Source of Ingredients) are added to milk and sugar, and the used, for a period not exceeding and specified in most laws. Egg yolk B. Same as I, B. mixture is cooked for a short time. seven days. may be either fresh, dried, or frozen. C. Same as I, C. This basic mixture is sufficiently 2. All products entering the ice (5) Harmless flavoring materials include D. Same as I, D. cooked when a thin film coats the ~re~m mix subsequent to pasteur the following : E. Same as I, E. blade of a knife when it is inserted IzatiOn should receive a germi (a) Natural : vanilla, cocoa, chocolate III. Nut ice cream is defined the same into the cooking mixture. B. Same I, C. cidal treatment comparable to pas coconut, fruits, fruit ·extracts, nuts, and as fruit ice cream except the following C. Same as I, D. teurization before they are added spices. should be substituted in A 4: D. Same as I, E. to the mix. (b) Artificial : imitation vanilla flavors A. N ot less than : · E. Bacteriological specifications. imitation fruit flavors, imitation nut and 4. 2 percentu~ by weight of sound VI. Bisque ice cream is a frozen des 1. The finished ice cream or ice maple flavors, etc. non-rancid nut meats, and con sert which may be defined the same as cream mix should not at any time ( 6) Harmless coloring materials include forms in name to the nuts and j or plain ice cream except that it contains· after manufacture have a stand the following: Burnt sugar or caramel flavors used therein. (See (9) in addition a bread or cake product. (See ard plate count in excess of 100,- flavoring, dyes certified for use in food under Source of Ingredients) classification IV.) 000 bacteria per gram. products which include the following: IV. Chocolate ice cream is defined the VII. Candy ice cream is a frozen des 2. The ingredients added to the ice Bl11e-indigo disulfoacid. Red-ponceau same as fruit or nut ice cream except that sert which may be defined the same as cream mix subsequent to its pas 3R, amaranth, erythrosine. Orange-or chocolate or cocoa are used as the flavor plain ice cream except it contains in ad teurization should not have a ang~ I. Y ellotli--naphthol yellow S, tar ing material. The minimum amount dition, candy. (See classification V.) standard plate count in excess of trazme, yellow AB, Yellow B. Grem that can be used is not set forth in most 5,000 bacteria per gram. guinea green, light green SF yellowish, VIII. Motisse is a frozen dessert made laws since the amount is variable depend fast green FCF. by whipping cream to the consistency of 3. The machinery and utensils used ing upon such factors as the quality of to make and store ice cream "whipped cream" after which sugar and (7) Appro·ved .ed)bl-e stabilizers include the chocolate or cocoa, the consumer should not contain more than 100 the following : Cielatin, gum tragacanth the desired flavoring materials are added preference, etc. The amount of cocoa India gum, and agar-agar. ' and to which fruits or fruit juices may bacteria per mi. when rinsed in a most commonly used ranges from 1.0 to standard amount of sterile water. (8) (a) Fmit includes the following: or may not be added·. This mixture is 2.5 percent, and for chocolate 2 to 5 then placed in a hardening room or SOURCE OF INGREDIENTS F:csh, cold-packed,_canned (either whole, perc;~ tum. freezing mi'xture and hardened. (1) Milk fat may be secured from any shced, or crus he&), pres.erves, candied V. Parfait (synonyms=French, New In practice it is made in either one of of the following sources: wholesome, un and dried. ' York, Neapolitan, or cooked ice cream) two ways : , adulterated cream and jor sweet milk (b) Fmit j11ices include the following: is a frozen dessert in which freezing has A. Th~ cre ~ m is whipped and the evaporated or condensed milk, dry cream: Frozen, canned or bottled, either con PHYSICAL REQUIREMENTS FOR FROZEN the weight have specified 1.6 pounCls, f r,v to exercise a great deal more ICE MILK 0 DESSERTS total food solids per gallon. be: nec~s.sa '' over frozen desserts to te 11 Some states, such as Arizona, Califor N!I'\'ISIO 0 . l I Recently it has been recognized that to SUr- h they fell mto the proper ega nia, Connecticut, Florida, Maryland, Mas control frozen desserts adequately it is AGITATION VERSUS NON-AGITAlFION whet er not. Furthermore, provision is sachusetts, and Wisconsin, define and per necessary to have physical as well as chem Many legal definitions do not state tl I~ or de in most laws for "imitation ice mit the sale of ice milk. Other states, ical requirements. This became neces manner of freezing frozen desserts. "Ev I(! no\\ ~a or other imitation products and such as Indiana, Kentucky, Michigan, sary when control officials found that a legal definition should contain a ~ry ream ew product does not fall into any New Jers·ey, New York, Pennsylvania, If lO)' n h . b frozen dessert could comply with all the constituted class, t en tt can e and Virginia, have no definitions cover tence or phrase to the effect tha ~ ' C:lur" n lega 11 Y . . .. chemical requisites and yet cheat the pub the manufacture freezing has Been tng bbcled "i.lllltatwn. ing frozen milk, but may or may not lic. This was possible because all the case of frosted malted milk the permit it to be sold as imitation tee companied by agitation of the ing ~ I n th e . . d o legal definitions pertaining to the chem ients." Unless this is done y,ou · 8 1 cream. ~ m3kers said that if tt co~tahme _ or istry of the product were on a percentage encounter trouble in keeping certain ty~ rcent butter fat by we1g t tt was too The range in the legal definitions for by weight basis while the product as actu of frozen desserts off the market ;wh" h p_e h According to C. S. Ladd, Food the milk fat in sherbets is from 2 to 3. 5 . h . IC ally sold was on a volume basis. Thus, can b e rna d e wtt out agttation. ~c ~issioner and Chemist for North percent by weight, and if total milk two five-gallon containers of ice cream To take care of certain types of frozen 0°kota, investigation showed that the solids are mentioned they range from having the same chemical composition desserts such as "popsicles" and the like . hness was due to too much sugar and not less than 4 percent up. The range could vary greatly in weight depending net to too much milk fat, and that when for milk fat in the legal definitions cov in _which agitation_ is not n~cessa ~y. and no .h. h upon the amount of air that had been in whtch are not agttated dunng freezing the sugat: was kept wtt ~~ t e proper ering ice cream starts at 8 percent by corporated in each during the freezing the words or phrase "during the manu: limits the¢ were no c.omplamts of exces weight as a minimum and has no maxi process. This point is very important to facture of which freezing has not been )t\'e richness. Thus tt would seem that mum limi·t. The minimum requirements control officials and one that is not gen accompanied by agitation of the ingredi. in this instance, the new product could for total milk solids in ice cream start at erally appreciated by a great many of ents". _could b~ inserted into the legal be made to conform w_ith existing !~ ws 16 percent by weight with no maximum them as yet. Only a few states have this definttwn. Thts would at least give ,1 without !i nj uring its qua!tty or palat~biiLty . specified. This leaves an open space under control. more concise legal definition and a gneater Whether this will be the case wtth all then between 2 and 8 percent for milk To correct this condition many states degree of control. new products remains to be seen. fat and 4 ·and 16 percent for total milk have placed ice cream on a definite weight However, the chief objection is that solids for · which there is no legally de per gallon basis. Some states stipulate OVERRUN IN FROZEN DESSER.11S m~ny of the ma~ers of froze~ desserts fined frozen dessert. Evidently some only the weight of the total food solids Another physic~l.,censideration is over ontaining less m~lk .fat than tee cream states believe that there is a place for icc per gallon, while others stipulate both run. In ice cream1 the overrun is .\CC hoping to capttahze on the fact that milk and accordingly have defined and weight and total food solids per gallon. between 80 and 120 percent. In sher hetr product resembles ice cream, and, legalized the product. States legalizing In the opinion of many ice cream men, bets it ranges between 25 and 50 per rherefore, the public will think it is ice products such as ·sherbet, ice milk, and only the weight of food solids per gallon, cent, while in ices. it approximates 2, rc. . m. ice cream where the chemical composi such as 1.6 lbs., should be specified in a percent. JS.toreover if the idea is to increase the tion of one product starts in where the legal requirement, and not the weight of NO MAN'S LAND on umption of milk products, then it other leaves off must of necessity do a the ice cream per gallon, such as 4.5 lbs. As new frozen desserts have >nrlPOI"Pn. lJnnot be done by putting less total milk great deiJ,l of control work to keep all the per gallon, nor the percentage by weight on the market, it became ~ li ds into a product. products within the prescribed legal lim of total food solids per gallon, such as many of them did not wi~h ex Another interesting thing brought out its, otherwise there would be a great deal 35 percent of total food solids. They isting legal definitions. A case in point by the development of frosted malted of ice milk sold as ice cream. Unless claim that the latter two stipulations favor is frosted malted milk. Here was a milk was the influence of the physical frequent chemical analysis were made of an inferior ice cream since the ice cream product which had too much milk £at to tate of t he product being sold upon its the various frozen desserts being made can be loaded with cheap materials such and sold in such states, they would be meet the requirements of a sherbet and legality. Malted milk as ordinarily made as sugar having a high specific gravity come a real bonanza for the "chiseler" not enough to qualify as an ice Gream. nd sold in the liquid state did not need whereas milk fat has a low specific grav In other words, the composition of it w a.~ and the unscrupulous manufacturer. In to comply with a legal definition, but as ity. They also have other pertinent ob such that it failed to comply with any of any event, legalizing ice milk would soon as a part of the heat ·energy was j·ections to these last two requirements. the existing legal definitions in many greatly increase .the load on any control However, the trend is toward a defi states, and as a result it became an "out· removed by refrigeration then it became agent and would require a more constant nite weight basis for food solids as evi law frozen dessert" in most states. $ubjcct to the frozen desserts law in many vigilance to protect the public adequately. denced by the fact that in 1936 sixteen The question now arises, what shall be ~.ties an8 came under the heading of ice The field .of frozen desserts is a large states had some sort of law regulating the done about such types of frozen desserts_? ream. Since frosted malted milk as one and is steadily increasing. Intelligent weight of ice cream. Total food solids Shall we revise our existing legal de6nt· commonly made only contained between legislation and proper supervision is apparently is the method preferred by tions, or shall we exclude them entirely ? inspector is essential for comparison with boat or directly into the dilution bottle. the former sample. The butter boat is placed in a test tube Notes on Microbiological Analysis of Ice Cream Samples may be removed from froz·en plugged with cotton and sterilized by dessert containers with sterile spoons, but heat before use. The width of the boat A. H. Robertson, Ph. D. ter triers or other similar suitable instru may be modified to fit within the neck ments. Spoons and triers may be placed of the dilution bottle. When weighing Stale Food Laboratory. Albany, N. Y . with handles outward in glass or metal ~he sample, the boat is adjusted so that containers and sterilized with heat. If 1t extends about three-fourths of an inch The volume of frozen dess·ert products representative sampling of bulk ice cream. preferred, they may be sterilized immedi out ?f the t·est tube. After weighing the consumed daily, the conditions under Although the mix is usually hdmogenized ately before removing the sample by portton needed to the accuracy of the which some of them are prepared, and before freezing, there is no assurance of dipping in alcohol and burning off the second dectmal place on a sensitive bal the fact that all are subject to contam the uniform distribution of the bacteria alcohol remaining on them. ance, slide the boat and contents out of ination somewhat similar to fluid milk, after ·entering the cans preparatory to Samples may be taken of unfrozen or the tube and into the dilution bottle con makes it pertinent in the interest of pub storage. Contamination from the frozen partially frozen mixe~ from the homo taining 99 mi. of sterile water. lic health that the manufacture and sale dessert container, although usually slight, genizer or the freezer by passing the Comparisons have been made between of these products be under sanitary super is not and cannot be distributed uniformly sampling bottle pnder the opening at the bacterial counts obtained at 3 2 o C. vision. Regulatory health officials, work throughout the frozen mass until the lat intervals during the discharge. If sam and 3 r c. both with the present stand ers at Agricultural Experiment Stations, ter has been melted and subj-ected to vig pling tubes are used to remove portions of ard nutrient agar and with the proposed and the organized industry have pion orous agitation. Similarly in opened mixes from cans or vats, the same care tryptone-glucose-skim-milk agar. The re eered in the development and application cans from which the retailer has removed should be exercised as when sampling sults indicate that if the product is of of sanitary methods of production and portions, surface contamination is not milk and cream. ~ood quality,_it will meet the present san sale. Both the ingredients before use redistributable uniformly throughout the For retail packaged samples and for Itary . regulatiOns ·even if the proposed and the retailed products have been ex mass. samples dipped from bulk by the mer agar IS used and the plates are incubated amined. The natural trend has been to The prevailing custom has been to re chant for the consumer, the portion at 32° C. In addition to the standard employ methods of examination similar move a surface portion from the frozen vended in its original container or a plate count of the bacteria in frozen des to those used for market milk products mass before taking a portion from be representative portion consisting of not serts, the·value of a test for the presence wherever it was practical. neath for the official sample. If either Jess than 50 grams after transferring it of coliform organisms is of additional aid Since ice cream is stored in a frozen the manufacturer or'· ) he retailer have aseptically to a sterile container, may be in determining the character and the condition and usually consumed before it been careless, there is no justification for submitted to the laboratory. All samples source of the contamination. There is has completely melted, it is natural to protecting their interests at the expense arc to be maintained at a temperature reason to believ·e that methods proposed expect fewer food poisoning outbreaks of the consumer. If careless methods not exceeding 40° F., and transported for the detection of certain pathogenic, associated with it than with fluid milk are prevalent, the evidence should not be pro• ptly to ·the laboratory. The samples thermophilic, psychrophilic, saccharo products. In spite of this, a number of diluted or removed.··· It is believed that are then melted, thoroughly and vigor serious outbreaks are traceable directly to the surface portion ·removed with thaf phjlic, and other types of bacteria that do ously agitated, avoiding churning of the not develop readily on standard nutrient frozen desserts. The need for pasteur which naturally becomes a part of it, fat, and portions removed for the neces agar as · applied to fluid milk and cream ization of the mix before freezing has usually to a depth of about an inch, is as sary tests. Usually the quantity of the been well established and most health reasonably representative a portion of the bulk sample is such ·that it can be melted may . be ~pplied with or without slight codes at present specify this requirement. frozen dessert ~bout to be consumed as by placing the container in water at 45 ° modl'ficattons to frozen dessert products. It is not the province of the Labora is possible to obtain under practical con,. C. (ll3° F.) for 15 minutes. Because High bacterial counts in frozen des tory Methods Committee for the Exam ditions. Certainly it might prove em the volume to be melted influences the serts may be caused by one or more of ination of Frozen Desserts to establish barrassing in a case of food poisoning time required for melting at 45 ° C., suit the following: standards of quality. Their activity is outbreak if litigation disclosed that the able representative portions of packaged 1. Inwedients ~f poor quality such as confined to the preparation of methods portion subjected to analysis had been samples may be removed aseptically at cream, mtlk, gelatm, frozen or powdered of sampling and of analysis, and to such selected to avoid surface contamination. th~ Ja?oratory also and prepared for anal egg, sugar, flavoring material, etc. suggestions as seem essential for the in If the extent of contamination attrib· ysts Identically as described for bulk . 2. Improper processing such as ineffi terpretation of the analysis. ut~ble to retailing operations is to be samples. cte_nt pasteurization, repasteurization, or Ice cream placed in packages by the determined, the vendor may be asked for On account of variations in the density agmg too long at too high temperatures. manufacturer for retail trade presents no a serving of the frozen dessert which, of frozen desserts, ·the volumetric meas sampling problem because the entire un after receipt, may be transferred asep· 3. Ineffective cleaning of -equipment ~rement of units for analysis is not con opened package serves as a sample for tically to a sterile container for laboratony sue~ as st~rage vats, homogenizer, pas Stdered satisfactory. It is recommended the laboratory. The inspector and ana examination. Obviously, a sample from teunzer, agmg vats, pipe lines, cans, etc. tha_t the desired quantity of ice cream be lyst are confronted with the problem of the bulk unserved ice cream taken by the 4. Careless employees who deliberately Wetghed aseptically into a sterile butter or through ignorance neglect to process S7 86 ANALYSIS OF IcE CREAM the mix properly or to clean the equip sarily indicate the presence of disease ment carefully. producing bacteria. A high count does mean general insanitation and the need Excessive numbers of bacteria in frozen Sediment Tests on Frozen Desserts desserts usually indicates a neglected for the examination of samples taken at product. Like milk, however, a low various stages in the process to determine M. E. Parker count does not necessarily mean a safe at what point the contamination is intro product and a high count does not neces- duced. Beatrice Creamery Company, Chicago, Illinois The sediment testing of milk as a bottle has contributed in hasbening the Septic Sore Throat Spread by Bulk Milk means of determining its physical con recognition of the sediment problem in milk is intended for cooking purposes. In tamination with visible and insoluble for market milk. Unfortunately, any exact (Editor: The following report of a mil~ eign particles is a practice which has been measurement of the amount of sediment borne outbreak of septic sore throat IS vestigation of this outbreak indicated that in abstracted from a report in the Baltimore the cafeteria, pasteurized milk from five-gallon efficacious in causing a reduction of dirt has not been practical on a quantitative Health News, July 19:>8. It illustrates cans was poured into pitchers and then into in any milk supply subj·ected to its scrut basis such as a gravimetric determination, the hazard that exists in the sale of bulk glasses prior to each meal, and the glasses were then placed on trays in a refrigerator iny during the past thirty-five years. because appearance has been the ultimate milk when the protection of pasteurization While it is a method with empirical lim criterion. Therefore, inasmuch as the and sanitary handling is viti~ted ~y co? until meal-time. The trays were then placed tamination of the milk durmg ats dis on the counter for distribution among the in itations, its simplicity in application and presence of macroscopic particles of vary pensing.) dividuals patronizing the cafeteria. At the interpretaton does guarantee its under ing size, identity and distribution is the An explosive institutional outbreak of 75 end of each meal, any of the glasses which had not been removed from the trays were standing and acceptance. In other words, essential prerequisite of a "sediment" cases of septic sore throat was traced to the dirt particles on a sediment disc is indis condition, it is probably futile to hope faulty handling of pasteurized m1lk del1vered emptied back into the pitchers, and these were in bulk to a cafeteria. The disease mamfest~d replaced in the refrigerator until the following putable evidence of their presence in for precision in evaluating the degree of itself by a severe sore throat m most m meal was served. This remaining milk and the sample of milk being tested, and sediment quantitatively. stances, by fever ranging up to 104° F., and additional milk were then used in the same manner as has been described. cons·equently the result is subject to no Attempts have been made to evaluate other characteristic symptoms. Only one case equivocation. There is, however, one the relative amounts of sediment in milk had a severe complication which was a late One of the employees serving in the cafe kidney involvement. The diagnosis of all :ases teria had been suffering with a sore throat fo il major objection to the sediment test. by the preparation of standard sediment were confirmed by positive laboratory findmgs. approximately three days prior to the sudden 'Fhis is stated fully and concisely in discs ( 4) showing definite amounts of There were no fatalities in this outbreak, and appearance of the first twenty cases of septic Standard Methods of Milk Analysis, sediment. In fact, an excellent set of sore throat among th ~, milk drinkers in the excepting for it the city record of no. known 1934, as follows : standard discs has been prepared and milk-borne disease since 1917 remams un cafeteria. This worker was examined at the time that the first cases became ill, and wa·. "With the development of efficient photographed ; by the Connecticut State broken. Epidemiological study of th~ outbreak made found to have a temperature of 102.8° F. H,'e single service strainers for use on Department of ·Health Laboratory ( 3) . it quite clear that the milk m questiOn had had a very severe sore throat with greatly dairy farms, and efficient strainers, As standards, it would appear that these enlarged and infected tonsils. This man was re cleJ at a photographic set of standards content. Milk, on the other hand, will inspection of the sediment found in densed milks can be satisfactorily tested once it has been adopted. What a pho normally have from 12V2 to 14V2 per frozen dess·erts, however, has been dem for sediment by applying the hot water tographic set of standards might lack in cent total solids; a variation of only 15 onstrated to be very similar in character method for frozen desserts. We have realism due to its "black" and "white" percent on the same basis. Accordingly to that found in market milk. Incident . . . . . ' not adjusted the amount of sample of character would be compensated for in preos10n tn companng 1ce cream to milk ally, this observation has been made on evaporated or sweetened condensed milks uniformity. Even if more realism might on a basis of total solids content is not ice cream samples examined from the in order to avoid confusion in the testing be introduced by deft color photography, to be expected. Even if we were to limit products made in practically all sections of these products as finished dairy pro it probably would be more confusing the comparison to milk solids (in the of the United States. Accordingly, there ducts. The same will apply to dry milks than the well defined "black" and case of ice cream) the variation in _com is no reason to suspect that there is any and butter. Dry milks or milk powders, "white" record. position will be approximately the same. need for different sediment standards for however, will require a different proce While it is true that the character of Assuming milk to have an average o ~ frozen desserts than would obtain for dure. The methods described by the the "dirt" normally found in milk and 13 V2 percent total solids content, a pint either raw milk supplies or market milk. American Dry Milk Institute (5) for cream might differ in some respects from sample would yield approximately 6] In other words, in comparing frozen spray, vacuum drum and roller process that found in some of the other ingredi grams of milk solids. Therefore, in or desserts with milk supplies, the essential powders are recommended. The method ents of frozen desserts- for example, der to get the same yield of milk solids difference in sediment is• one of degree for the sediment testing of butter, in flavoring extracts, emulsions, stabilizers, in an average ice cream or mix of 38 per and not in kind. ~luding the hot water and acid procedures, etc.- the fact remains that any extraneotts cent total solids content containing \2 2 In the sediment testing of stabilizers, a IS suggested as adequate for this ingredi· or foreign material found in such ingredi percent milk solids, a 280 gram sample 11/z gram sample is recommended. This ent of ice cream or as a sepa·rate dairy ents can be estimated and classified simi would be necessary. Such a samg1e represents the ~axir~mm concentr~tion product (6) (7). Incidentally, the Food larly to the manner employed in the sedi would be approximately 10 percent which would ordmanly be found m a and Drug Administration of the United ment testing of milk. As a matter of heavier than one-half p.int of such iee pint sample of ice cream. States Department of Agriculture has de fact, in the examination and classification cream mix weighing 9 pounds per gallon. Salt, sugar, inert sugar, syrups, as well veloped a method for the detection and of the sediment discs obtained from test When other types of frozen desserts otfier as the water used in making syrups and identifying of extraneous material in but ing frozen desserts and its ingredients than ice cream are considered, the varia in washing the equipment can all be tested ter which is designed primarily for pur other than milk or cream, extraneom tions in composition indicate the futility for sediment by applying the hot water pos·es of prosecution in the enforcement matter only can be classed as "dirt" or of using a sample of a specific weight method described for the finished frozen of the Federal Food, Drugs, and Cosmetic sediment. Fruit fibers, seeds, nuts, etc., which will give an exact comparison w.ith desserts, except that 50 gm. samples are Act. cannot be considered as sediment if the milk on a milk SQl~ds-·oasi s . InasmuG as recommended instead of the pint samples In the sediment testing of frozen des frozen dessert is flavored with fruit or a pint sample is dsea in sediment testing cecommended for frozen desserts. By serts and their ingredients, we have en nuts. Therefore, they would be excluded of milk, due probably to considerations using 50 gm. samples of sugars and syr deavored to retain substantially the same from the sediment test unless the flavor of convenience, perhaps the same prin ups, the results obtained will be repre method which has been applied to milk ing materials can be successfully screened ciple should apply .in the case of £rozen sentative under all conditions of the so successfully. The suggested proce out or the fibers, nuts, seeds, etc., identi desserts. Therefofe; · a half-pint sam:ple a'!!_o~ of these ingredients which would dure or modi•fications for the ingredients fied by careful examination with proper of mix or a pint sample of the Frozen ordinarily be found in any frozen dessert. so far considered have retained the essen magnification. dessert is suggested as the most practical Extracts are readily tested for sediment tial features of the suction or pressure The sediment in frozen desserts can be solution to what otherwise can pro:v.e a without any treatment whatsoever al type of sediment tester and the use of determined by either the hot water or the complex mathematical problem. 'J.lhe though applying the hot water method standard lintine discs. In determining soda method (8). However, a 100 gram greater volume of the froz·en dessert described for the finished frozen desserts the extraneous matter in fruits, nutmeats sample is not recommended inasmuch as sample, as compared to the mix saamle, is recommended. The ·extracts will ·tint and purees or ground fruits, we have the sediment test as applied to milk is is necessary due to the fac1t that thete i, the sed iment discs, but this does not in found it possible also to retain the same based on a pint sample. It would, there approximateLy a 100 percent increase in terfere with the examination for sedi features, providing thes·e samples were fore, appear desirable that frozen desserts volume (overrun) during the freezin ment. Extracts which have been tested properly prepared. In such work, we and their ingredients be subjected to simi of such products in order to render tihem with satisfactory results include vanilla, have found the flotation procedures of lar conditions in order that an equitable palatable. va~illin , orange, lemon, and maple flavors. B. J. Howard (1) (2) of invaluable as comparison may result. Normally, ice In the examination of frozen desserts, It 15 not possible to specify any amount sistance in preparing such products for cream will vary from 10 to 14 percent in we are concerned with a variety of" 1rnilk of sample of extracts which would be the sediment test. butterfat; from 9 to 11 percent in serum products which have undergone vanyJns representative of the amounts contained In all the methods outlined, we have solids; from 14 to 16 percent in sugar; degrees of processing; whereas, in ma~ket in a finish ed frozen dessert because of endeavored to retain the essential "modus the infinitesimal quantities that would be from lf4 to y2 percent in stabilizers, and milk, we have a product of more limited operandi" of the s·ediment test as it is from 0.3 to 0.6 percent in egg solids. processing. Therefore, we should nor· mvolved. Therefore we have recom applied to milk. Actually, our reason is This means that ice cream will vary ap mally expect the s·ediment condibion of mended the testing of' these products the that it ·is generally recognized that the proximately 25 percent in its total solids frozen desserts to be comparatively bett~r s me as for sugar, syrups, etc. sediment test has been the means of de content based upon the higher total solids than that of market milk. Mic;roscop'' Evaporated milks and sweetened con- veloping a more sediment free, cleaner 90 SEDIMENT TESTS milk supply in the past thirty-five years. to assume that similar results might be It is true, of course, from the derivation expected in applying it to frozen desserts of the word "sediment" (L., sedimentum and particularly to the ingredients of -a settling; fr. sedere-to sit) that we frozen desserts heretofore not so scrut Three Associations Standards are . concerned primarily with particles inized. "Seeing is believing" or as the whtch settle. Webster confines the defini Chinese say: "One picture is worth ten tion to "the matter which settles to the thousand words." In such philosophy is A ray of sunshine for those who have union for sanitary pipe lines, (2) bottom from a liquid." Technically, found the virtue of sediment testing., been decrying the lack of uniformity in threaded .fittings including bends for use therefore, tliere would be no sediment in the field of milk sanitation may be seen with this union, and (3) improved indi a frozen dessert inasmuch as it is a semi REFERENCES in the recent inauguration of a program cating and recording thermometer con plastic mass whose physical state would by cooperating committees of three asso nections for vats and for pipe lines. De 1. Howard, B. J., U. S. D. A. Food and Drug ciations for the standardization of designs tails of these accepted standards were ~inimize or prevent any settling of par Administration Fig Testing. July 1, 1929. ticles. On the other hand, the "sedi 2. Howard, B. J ., U. S. D . A. Food and Dr.ug for commonly used items of milk plant shown in the November, 1938 issue of ment test" as we know it is, accurately Administration Walnut Testing. July, 1930. equipment. this journal. The above thermometer .fit speaking, a confusion in nomenclature. 3. Laboratory Manual. International Assoc.ia, General recognition of these accepted tings are illustrated in Fgures 1 to 4. · tion of Milk Dealers, 1933. standards by health officials, milk deabs, In applying the same to milk, we do not 4. Standard Methods of Milk Analysis, Ame~;J . It is obvious that it will take months actually cause any settling of particles, can Public Health Association, 1934. and equipment manufacturers is urged for manufacturers to get the new stand but provide essentially a procedure for 5. The Grading of Dry Milk Solids. Amerj!1aQ officially by these committees. ards into production. In the interim, Dry Milk Institute, 1936. The coop ~ rating agencies are the Com present standards should be accepted. physically removing extraneous matter 6. Stewart, G. F., A National Survey of Meth. from the liquid which is collected on a mittee on Sanitary Procedure of the Inter ods for The Determinat-ion of Sediment io national Association of Milk Sanitarians*, As soon as the new equipment is avail filtering substance whose white character Butter and Cream. J. Dairy Science 20 8 able, each committee will urge its con provides a contrasting medium for ac 509-519 (1937). ' ' the Simplified Practice Committee of the: 7. Laboratory Manual. American Butter Insti. International Association of Milk Deal stituents to produce, accept, and demand centuating the dirt particles contained in tute, 1937. · standard equipment as the case may be. the liquid being tested and which are re ers,** and the Technical Committee of 8. Report Joinf Committee for Analyziog Of cours~ it is expected that additional tained on the filter surface. Frozen Desserts, A. P. H. A. Yearbook, the Dairy and Ice Cream Machinery and 1937-1938. Supplies Association.*** items will be standardized from time to Simplicity in operation and interpre , ... tation has been the major reason for the To date the committees have accepted time as such items are presented to the committees for consideration. successful application of the sediment Editor's Note: Thel· ::n:her papers that 'Were standards for (1) a recessless sanitary p_resent.ed at the . Syptposium will be pub testing of milk. It is, therefore, logical lashed m the May •ssue of this Journal. Photographs by Courtesy of Taylor Instrument Companies. I'IGUII.B 1 . T emperature T u b e System with 3A Type RN sanitary fittings for installation in j. cketed vats and tanks. 92 THREE AssociATION STANDARDS JoURNAL OF MILK TECHNOLOGY 93 *MEMBERSHIP oF CoMMITTEE oN SAN· ***MEMBERSHIP OF THE TECHNICAL ITARY PROCEDURE OF THE lNTERNA· COMMITTEE OF THE DAIRY AND leE TIONAL ASSOCIATION OF MILK SAN· CREAM MACHINERY AND SUPPLIES ASSO ITARIANS. CIATION (NOW THE DAIRY INDUSTRIES C. A. Abele, Montgomery, Ala. SuPPLY AssociATION) . Loomis Burrell, Little Falls, N . Y. G. W. Putnam, Chairman, Creamery Pack W. D. Dotterrer, Chicago, Ill. age Mfg. Co., Chicago, Ill. H. C. Eriksen, Santa Barbara, Cal. Leslie C. Frank, Washington, D . C. E. R. Alling, Rice & Adams Corp., Buffalo, George W. Grim, Ardmore, Pa. N . Y. Ralph E. Irwin, Harrisburgh, Pa. Loomis Burrell, Cherry-Burrell Corp., I:.i ttle John A. Keenan, Boston, Mass. Falls, N . Y. Paul F. Krueger, Chicago, Ill. F. G. Cornell, Jr., Jensen Creamery Machin ~ M. E. Parker, Chicago, Ill. ery Co., Inc., Bloomfield, N. ]. Sol Pincus, New York City. Timothy Mojonnier, Mojonnier Bros. Co., Geo. W. Putnam, Chicago, Ill. Chicago, lll. W . D. Tiedeman, Albany, N . Y., Chainnan. C. M<>rtensen, Standard Milk Machinery Co. **MEMBERSHIP OF SIMPLIFIED PRACTICE Louisville, Ky. ' COMMITTEE OF THE INTERNATIONAL R. E. Olson, Taylor Instrument Companies, ASSOCIATION OF MILK DEALERS. Rochester, N . Y. A. H. Luedicke, Gridley Dairy Co., Inc., C. A. Rogers, C. E. Rogers Co., Detroitl Milwaukee, Wis. Mich. F. E. Goldsmith, Borden's Farm Products R. C. Strachan, The Pfaudler Co., Elyria, Co., New York, N. Y. Ohio ]. L. Jones, III, Supplee-Wills-Jones Milk Co., Philadelphia, Pa. R. V. Thomas, York Ice Machinery Corp., F. H. Kuhlman, Jr., Bowman Dairy CIJ., Canton, Ohio Chicago, Ill. Theodore Thompson, Emery Thompson Ma G. L. Nourse, H. P. Hood and Sons, Inc., chine & Supply Co., New York, N.Y. Boston, Mass. H. S. VanBomel, Sheffield Farms Co., New W;. ... D. - TIEDEMAN) York, N.Y. ·• ,·' . Chairman. FIGURE 3. Industrial Thermometer with 3A Type RN sanitary fittings for installation in jack eted tanks and vats. FIGURE 2. Temperature Tube System with 3A Tyne RN sanitary fittings for installation io milk lines. These fittings are provided with special adapters for various sizes of PrGURl! 4. I?dustrial Thermometer with 3A Tyne RN sanitary fittings for installation in milk piping. hoes. These fittings are provided with special adapters for various sizes of piping. lHREE hSSOCIATION ;,TANDARDS }OURNAL OF MILK TECHNOLOGY 95 3A TYPE:: R.N. THE:.RMOMETER FITTING REMOVABLE UNION !I FOR PIPE UNE.S 3A TYPE:: R.N. RE.CORDING THERMOMETER .,F.J·1T IN G SHOWING REMOVABLE. UNIO~ NUT Photograph by courtesy of American S & B Instrument Division, Manning, Maxwell, & Moore, Inc., Bridgeport, Conn. FIGURE 6 Mauner of Removal of U11io11 Nut over Fermle SANITARY fiTTINGS, lf&i SAME. 11::> . The improved indicating and record A newly designed union nut has been FOR PIPE. LINES mg thermometer connections ar-e illus accepted for removing over the ferrule Drawing by courtesy of American S. & B. Instrument Division, Mannln ~rated in Figures 1, 2, 3, and 4. In each and stem of the thermometer. This is Maxwell & Moore, Inc., Bridgeport, Conn. Instance, the union nuts are taken off over illustrated in Figure 5 and Figure 6. FIGURE 5 the thermometer scale case. Editor Drawhzgs of Removable Uni011 Nuu ui meat. The vats were rinsed amounted to 1456 pounds, and it tested e Of course, it is necessary to adhere to chemist in ~rder to make microscopic specifications governing physical condi counts and simple field tests and inter tion of establishments and their equip pret the results, and to understand lab Administration and Procedure in the Enforcement ment, in order to make possible sanita oratory ·reports of analyses. He should of Milk Regulations tion and satisfactory operation, and also be a psychologist and educator of suffi to guide the industry and to provide a cient ability to sell himself and his milk John L. Rice, M. D. means of uniform enforcement for the control program to producers and dealers inspectorial personnel. of milk. He must have poise, alertness, Commissioner of Health, New York City It might be well to mention at this and at _times a knowledge of court pro point that we have found it advisable to cedure m the event that court action be require plant operators to submit for our comes necessary. The enforcement of milk regulations in phases: (a) country or source of supply approval blue prints of all proposed new Among other matters to be considered this State is thoroughly accepted and is a control, (b) city or point of distribution construction or major alterations. This in the administration of a sound milk matter taken for granted. This is a clear control, and (c) laboratory control. Of eliminates the necessity for future expen pr?gram is the necessity of having suf sign that on the whole the administration course, the size of N ew York City neces sive modifications due to failure of com fiCient personnel and facilities to do the of the sanitary control of milk has been sitates a large staff for the work, but the pliance wi_th our r ~gulations. We speci work properly. Dr. Wilson G. Smilie, reasonable and based on common sense. principle of checking the three phases fy that wntten approval be obtained from in his book on "Public Health Adminis In the long record of freedom from milk mentioned also holds good for smaller us before installing new equipment in tration in the United States," says that a borne outbreaks, at least as far as the municipalities, even though one man may plants, etcr' Many insanitary features municipality of 100,000 people would larger communities are concerned, there take care of more than one of the phases which had hitherto been carried from require two milk inspectors. Due to the is proof that the high standards that have involved. year to year, have thus been corrected, and large concentration of population in New been set have been fully warranted. For Milk control should primarily be di it is very gratifying to note that we have York City, we are able to carry on by tunately, we here, different from the case rected to the field examination of the received a high degree of cooperation having two milk inspectors per 225,000 at present in England, are long past product itself for safety and sanitary qual fro m both the milk dealers and the equip population. the stage where health officials are called ity, and to the supervision of the produc ment makers in this program. I. know .?f no official city budget that upon by the producers, the dealers, or tion, processing, and distribution of tfie Such procedure not only aids the De ~ames an Item for milk inspection that the public to present a justification for milk ; and secondarily, to the physical partment of Health in predetermining IS large ·e.nough to assure by itself, com sanitary milk regulations. Our discus condition of establi~ments and equip that the plant or equipment will be satis plete, satisfactory supervision of a milk sions concern themselves with specific as ment. The improvetnent brought about factory, but it also serves to assure the op supply. The operators themselves have a pects regarding the manner of administer through the field examination of the erator that he can safely proceed with the real _responsibility in ·supervising the pro ing the control or to particular require product is well illustrated in our own construction work and installation of ductiOn and. handling of their own prod ments, while the main basic principles, City of New York where foll~wi~g the equipment without fear of having new ucts. . Vetennary examination, dairy in sanitary milk production, pasteurization, introduction of the .rtfeck exammatwn o~ chan s forced upon him soon after com spectiOn, deck examination of milk and and direct safeguards to eliminate contam milk in 1936, the logarithmic averages oB pletion of the work. b_acteriological control of products c~n be ination or the possibility of spread of dis standard plate counts of Grade B raw To carry out efficiently such a program, o_ted as ~xamples of this self-supervision. ease, go forward unchallenged. milk were reduced from 140,400 per ml. it becomes increasingly apparent that the Smce the operators and their supervisory The machinery set up at the beginning in 1935 to 85,600 in 1937. We all kn0w milk inspector has to be a person of ·employees are essential factors influenc of milk control in some respects was crude the many improvements brought about in high ly specialized ability and training ing milk qualii:y, it is important -that care and haphazard. Pasteurization control the efficiency of pasteurization after the who must devote full time to the prob ful consideration be given by the dealers was very inefficient. A great portion of recent introduction of the phosphatase lem of safeguarding the milk supply. to the qualifications of their personnel the work was directed toward detection of test. Such field tests not only make it 'Ilhe inspector has to be enough of an and the character of operator or manager. frauds, such as the addition of water and possible to exclude unfit and unsafe prod architect to give advice on the construc It is frequently necessary to carry on chemical preservatives. However, with ucts from channels of trade and con tion and layout of a milk plant, and educational activities among producers and sumption, but they also have educational :nough of a mechanical ·engineer to pass the advancement of knowledge and ex dealers to get them to adopt procedures and psychological value. These tests con· Judgment on the sanitary construction and perience, greater emphasis was placed on and methods found advisable by enforce the more direct health aspects of the milk vincingly illustrate to the producer or proper operation of milk equipment. He ment authorities. Every minute' matter control program. dealer the fitness or unfitness of the prod· sho uld be enough of an expert on water uct. The fact that any inspector, through supply and sewage disposal, at least to ca~not be made the subject of legal regu Our experience in the enforceme~t . of latiOn and there has been considerable milk regulations has caused us to diVIde the use of field equipment, can in a ·few h a:~ sufficient ability to detect irregu· the work roughly into three distinct minutes determine gross irregularity, has lan~ 1es , and understand the operation and success in having dealers voluntarily a tendency to discourage violations of the S~llltary precautions for the relatively adopt procedures upon our recommenda Delivered at the 12th Annual Meeting of the New regulations or attempts to deliver 1poor s•mple water or sewage plants. He must tion. We generally find it desirable to York State Association of Dairy and Milk In· spcdors, at Rochester, N . Y., Sept. 16, 1938. quality milk. to some extent be a bacteriologist and hold meetings with the milk and asso- 102 MILK REGULATIONS 103 ciated industries to get their reaction to Today, as in the past, the I?rim~ry proposed new procedures or changes. task of health departments in the~r milk Within the department also we have control activities is concerned w1th the the necessity of a continued personnel assurance of a safe and wholesome milk Abstracts of Technical Papers Presented at Thirtieth Annual Meeting educational program. Inspectors are usu supply, and yet the time has ~~rived of the American Butter Institute ally busily engaged in their work . of when we must realize and be s·ens1hve to checking plants and products, wh1c_h the point, that in the whole milk picture November 29-30, 1938, Chicago, Illinois. tends to become routinized. Unless their there is an economic phase that is very attention is called to new developments troublesome and important. We should Reported by M. E. Parker and procedures by means of periodic con be quick to understand that the producer ferences, association meetings, discussions has to make a living, and the consumer's by specialists and resear~h work~rs,. pub ability to buy is not unlimited. Health lications, etc., an inspectiOn serv1ce IS apt department personnel should be eager to to find itself antiquated, left behind by cooperate whenever possi_ble with . o~~er the march of progress. The staff, by agencies who have the mam resp~nsibdit}l Copper Contamination keeping mentally alert and ge~eraJiy for this phase. More than ever m carry E. H. Harvey aware of new developments, mamtams ing forward our activities for safety and its status as a missionary for advancing wholesomeness of milk, we should have Dr. E. H . Harvey, Chief Chemist of procedure. (More co11jirmatory data ap milk sanitation. in mind economics. While we should Wilson & Company, discussed the re Just as it is necessary to have cooper never compromise with adequate stand pears. to be 11e'"essary before this can be sults of applying HarraH's modification defimtely established as othe1· investi ation between the industry and the health ards for safety and wholesomeness, we of the Ritter test for copper in milk gaton kav~ noted ~ome tmexplained dis department, so is it essential. for a suc should always be sure that our regulat whereby butter is tested directly without cessful administration of a milk program ing administration and our control pw crepancres rn applymg the modified Ritter ashing or separation of the fat. Quanti test of Horrall to btttter.--Editor's note.) that the local, state and federal agencies cedure are free ·from fancy work that is tative determinations of copper using the The. retardation of changes (peroxide concerned work together on ~heir mutu~l expensive and cannot be justified. method of Williams indicated that the formaho.n and development of tallowy problems. A go_od ~llustratwn of th1s I wish to emphasize one of my earl~ modified Ritter test will react positive to flavor) mduced by copper contamination kind of cooperation IS the arrangement statements concerning_ the application o ~ 0.4 ppm or above. It was also ascer of_ butter was found to apply to ascorbic between the New York State and New tained that this test is inactivated by the common sense in "the enforcement of aCid and ethyl tyrosine while common York City Health Departments, whereby milk regulations. Strict adherence to the presence of Vitamin C (not a factor in the former checks and reports on water creamery butter) while the presence of a a~tio~i?ant~ such as vegetable lecithin, letter of the law combined with rigid mcot1mc aCid, and oat oil were found to supplies at our country milk plants, and large amount of peroxides will give a policing is one method of procedure, bu ~ be of no value. Oat flour maleic acid also through local and district health false p sitive test (not a serious defect the procedure whidl- obtains results with and aqueous extracts of o;t flour com: officers determines whether the state and inasmuch as butter becomes inedible with a minimum of hardship and without SM pletely retarded peroxide formation but our city regulations are met in the ev~nt the development of any appreciable per of contagious disease cases on dauy rificing principles is the better one to oxide value) . introduced characteristic off-flavors which render them of doubtful value. farms. follow. In a series of experiments using cop The exposure of cream to copper par per lactate as the contaminating factor, ticularly in forewarming vats (which ap it was observed that after the inoculated pears to he the most common source) is samples had been incubated at 21 o C. for indicated to be a doubtful production 7 days. an inordinate drop in score re practice, as isolated samples of butter sulted when more than 0.3 - 0.5 ppm of copper was added to butter having an have been found with a copper content initial score of 92 points and giving a of as high as 8 ppm, such butter inci negative modified Ritter test with an dentally developing tallowy flavors rap a<1tua l copper content of 0.075 ppm. idly although no bleaching or rancidity When the addition of copper lactate ex occurred. Initial churnings invariably ceeded 1 ppm, definite tallowy flavors show more copper than later churnings were noted, and an excessive drop in while the last churnings may be almost scor~ res~lted. Accordingly, the Horrall free of copper in creameries where there modificatiOn of the Ritter test appears to is a moderate amount of ·exposed copper be of possible value as a quality control in their equipment. {To be continued in Ma)' imte) 104 JouRNAL OF MILK TECHNOLOGY 105 JOURNAL OF MILK TECHNOLOGY JN:fERNATIONAL ASSOCIATION OF MILK SANITARIANS Official P11blication of the ·J~ Victor M. Ehlers - ···-·--···-·······--·-···--····--···---·-·- ··- ··-·················---·Austin, Tex.; 1 111 International Association of Milk Sanitarians ' "d nr Paul B. Brooks M. D. ·-·····- ··----·-··-- ...... Albany, N. . '" t J'tct:Prl1ptl eid~nl• Leslie C. F~nk ····· ······ · ·· ···-··~-·--· ·· - ··· - ··· · · ·· · · W as hington, D. C. (Association Organized 1911) d lt(t• res ' - " - L1 . M'cb 11 p ·de•tt Dr Fred W Fab1an ...... ·· ·· · ··· ·· ··-· -··-·· · - -~st · nsmg, 1 . Office of Publication 29 :'iT. Day St., Orange, .X. J. itirJ rite- re.sr ,, , : · r .Treamrer, C. $Jd nf}' Leete, . , 1111 > State Department of Health, State Office Bw!dtng, Albany, N. Y. Also designated official publication of New York State Association of Dairy and Milk Inspectors NEW YiORK STATE AssOCIATION OF DAIRY AND MILK lNSPECfOR,S Massachusetts Milk Inspectors' Association P,IJ.IJenr, c. L. Kern, D.V.r..L --·-·····- ·· -·· ····· · ····-···· ··· -·········· · --···· · · --·-··· - · · ·- ·-··~e w York, N. Y. Central States Milk Sanitarians , ct·PresiJent, E. E. Brosnan : ·······-···-···-----·--···-·--···---····-···········-··· Bmghamtoo, N . Y. 1 rrreasm-er W. D. T1edeman, Connecticut Association of Dairy and Milk Inspectors f('ftlttr1· ' · State Department of Health, State Office Building, .Al:bany, N . Y. Metropolitan Dairy Technology Society Chicago Dairy Technology Society MASSACHUSETTS MILK INSPECTORS' ASSOCIATION Indianapolis Dairy Technology Club ,., ,.mr,·J c. ·J.rr Kimberly ·- ········-·-··------··---·--·--·-·---·New York, N. Y...... reasurer, 0 . F. G;urett --· ··-··· ············-······ ····· ··Rutgers University, New Brunswick, N. ]. ttrttar) ~· . . E L . M"ch T ,,J Vice·Preride111, Fred W . Fab1an ····-· --···--.-··-·- ··- ·····--·····--···-····-··· nst nnsmg, 1 • Editors W. B. PALMER, Managi11g Editor J. H. SHRADER, Editor CENTRAL STATES MILK SANJTARlANS Orange, N. J. East Orange, N. ]. Associate Editors fmiJ•m 0liver C. Hutter - ········- -···-·-···-·--··-···-·----·---. ...Lake Geneva, Wis. fmt Vi:e-Pre.riderll, Peter C. Larson ····-···--·--··-·················- : ····-··--·····--········Ch.icago, ni. ABELE C. A. J. A. KEENAN H. N. PARKBR StcrJtld Vice-President, Leo Randolph -- -- ···· · ··-·· · · · ····---- · - ·····------·-- - -·-- ···· · ·-·-- ·· Cbi~go, Ill. Montgomery, Ala. Boston, Mass. Jacksonville, FJa. Third Vice-President, John C. Krueger ······-·········- ··················-············· ····-···················ChiCago, Ill. SARAH VANCE DUGAN C. K. JOHNS .. , ~-E. PARKBR Sttrltar)·Treasllrer, Domt ld V. Fitzgerald ...... P. 0 . Box 295, Elgin, IUioois Louisville, Ky. Ottawa, Canada Chicago, Ill. J. G. HARDENBERGH ERNEST KELLY G. W. PUTNAM CONNECTICUT AsSOCIATION OF DAIRY AND MILK lNSPECfORS Plainsboro, N . J. Washington, D. C. Chicago, Ill. p,,J~. W. H. Fris bie ······---···········--········ --· ·········· ·····-··- ·---·-·-···-······--··-····Stamford, Coon. M. A. HEINZMAN P. F. KRUEGER . I -- F. M. SCALES r.~t Vire-Preside11t, Dr. f. R. V:~il ...... Bcistol, Conn. Ventura, Cal. Chicago, Ill. New York, N. Y. ff~/IJ Vice-President. B. E. Boweo_ ...... -...... Waterbury, Conn. H. R. THORNTON ThhJ Vice-Presidmt. H. Clark ...... :·············-·· ··········Colchester, Coon. Edmonton, Alberta, Canada S trttary-Treasurer, H. C. Goslee ...... State Offici:- .Building, Hartford, Conn. The JOURNAL OF MILK TECHNOLOGY is issued bimonthly beginning wjtfl, the METROPOLITAN DAIRY TECHNOLOGY SOCIETY ary number. Each volume comprises six numbers. It is published by the International .cu,>u.,,. .. of Milk Sanitarians, and is printed by The Chronicle Press, Inc., Orange, N. ]., U. S. A. '"'''' "'· ll>r. C. H. Kimberly ...... New York, N . Y. Subscriptions: The subscription rate is $3.00 per volume. Single copy, 60 cents. tcfllary-lfreas11rer, Dr. 0 . F. Garrett ...... Rutger s niversity, New Brunswick, N. ) . Advertising: All correspondence concerning advertising, reprints, subscriptions, and other business matters should be addressed to the Managing Editor, W. B. Palmer, 29 CHICAGO DAlR Y TECHNOLOGY SOCIETY Day Street, Orange, N. ]. Manuscripts: All correspondence regarding manuscripts, editorials, news items, ,,,,;;/till, V. Christiansen ····- -·····-···-··-······················ ---- ·································· ··········Chicago, Ill. ments, and other reading material should be addressed to the Editor, ]. H. Shrader, .}.39 1••~Jurer, Dr. Gus Ulvin ·· ··· ···- ····-····· ·---·· ···--·······--·--············---··--· ······-·-···-··············Chicago, Ill. dale Avenue, East Orange, N. ]. uttary, Dr. P. H. Tracy ...... Dairy Department, University of Ill.i.nois, Urbana, Ill. Membership and Dues: Active and Associate Memberships in the Association ue per year. This includes all issues of the Journal. All correspondence concerning me~:rsb~P.~ INDIANAPOLIS DAIRY TECHNOLOGY CLUB the INTERNATIONAL ASSOCIATION OF MILK SANITARIANS, including appu~a••v ... membership, remittances for dues, failure to receive copies of the JOURNAL OF MILK tr 1idn1t1 Walter Roberts ...... - ...... Indianapolis, Ind. NOLOGY, and other such matters should be addressed to the Secretary of the .n»u~o~•'""'!! frttary, Dr. E. H. Parfitt ...... Purdue University, Lafayette, Ind. C. Sidney Leete, State Department of Health, Albany, N . Y. JOURNAL I Association News of INTERNATIONAL ASSOCIATION OF MILK MASSACHUSETTS MILK INSPECTORS' SANITARIANS AssociATION MILK TECHNOLOGY 1 The 28th annual meeting of the In At the annual meeting held in \Xl'or. ternational Association of Milk Sanitar cester, Mass., on January 4th and 5th, the Volume 2 May, 1939 Number 3 ians will be held in Jacksonville, Florida, following officers were elected: on October 25, 26, and 27. Mr. H. N. President, Edward J. O'Connell, liluJ. Parker of Jacksonville has been appointed yoke, Mass. Vice-president, John B. Enright·, Ritch. chairman of the local committee. The Editorials burg, Mass. headquarters hotel will be announced Secretary· Treasurer, Robert E. Bemis, Tbe opinions and ideas exp1·eued in papers and editorials are those of the respecti11e authors. The expressions of the Auociation are completely recorded in its transactions. later. Cambridge, Mass. The program of this meeting will con Executive Committee : tain some items of unusual interest. No A. R. Tolland, Boston, Mass. milk sanitarian can afford to miss it. Plan George D. Melican, Worcester, Nfass. An Institute to Appraise Equipment Performance now to attend. George A. Flanagan, Lynn, Mass. Many papers and committee reports have been presented at meetings of milk Back copies of the annual reports oi Patrick C. Bruno, Revere, Mass. dealers, ice cream manufacturers, milk sanitarians, public health engineers, and health the International Association of Dairy R. E. BE¥is, officers, describing the application of new control procedures or the performance of and Milk Inspectors for the years 1927, Secrefm·y-Treasllrer new dairy plant equipment. A survey of any milk equipment exposition reveals the great differences of opinion as to the kinds of equipment that are believed to be the and 1929 to 1936 inclusive may be pur· Certain Dairy . Products ExempteC! from best for handling certain operations. Manufacturers of dairy machinery, concerns chased, as long as the present supply is furnishing laboratory apparatus and materials, and producers of various supplies make available, at a price of $5.00 plus postage Immediate Formulation of Federal Standards strong claims as to the excellence of their products in tJ1e fields of their respective for the set, or for single copies $1.00 in. Under the provisions of the new pplications. However, the determination of compliance is left to the individual eluding postage. Food, Drug, and Cosmetic Act, the j11 dgment of each purchaser, interested milk sanitarian, or control official. c. S. LEETE, of Agriculture is " a ~thorized to p~ u!mu•ga•:r. The Committee on Sanitary Procedure of the International Association of Milk Secretary-Treawrer reasonable definitions and standards $3nitarians, in collaboration with the trade associations, is expected to reduce much for any food under its common or usual In the absence of such definitions, any of the confusion (1, 2, 3) . However, its work as now projected lies in the field of that contains two or more ingredients only designating the principles that should be incorporated in design. It calls atten NEw YoRK STATE AssociATION OF declare them on th ~abel. Inasmuch tion t eeded developments. It "accepts" designs of construction. However, it Secretary has not yet had time to does not attempt to specify details. It is unable to determine performance and de DAIRY AND MILK INSPECTORS standards for all such foods, he has exemption for a period of two years grees of compliance with claims of manufacturers. The judgment of experts is high· President Kern expects to call a meet number of foods including the r.:>llowing ly desirable to point out existing needs, to indicate where new developments are ing of the Executive Committee in the products: necessary, and to generalize on design. Their work v,:ould be greatly facilitated, near future to discuss the program for the Evapontted milk Cheeses howcver1 and their findings far more authoritative if physical means were provided Sweetened condensed Oleomargarine for determining whether particular equipment and supplies actually do comply with next annual meeting. Suggestions from milk Sweet milk members as to subjects they would like to Malted milk Milk bread the claims of their producers. hear discuss·ed are invited and should be During this period, the above foods Such a service should not in any way conflict with the work of laboratories en Pfed in research on dairy equipment, as for example, the engineering laboratory for forwarded to the secretary. empt from a declaration of each although it does not exempt them dairy equipment research in the National Institute of Health. These latter serve as the presence of any artificial fla~ormg, bluable sources of information for the above committee. When these laboratories W. D. TIEDEMAN, coloring, or chemical preservative. . governmental, they usually are not authorized nor are they interested in under Sec1·eta1-y-Treasttre1·. ]. H. SHRADFI ~g performance studies on all pieces of equipment that are offered, and in issuing •ficates showing the degree of compliance with published standards. The same which now is used in certifying colors for use in foodstuffs should be more applicable in certification of bacteriological culture media, incubators, and labOratory supplies. The service would show whether any product does or does meet accepted standards. The claim of a manufacturer that his model of pas-