L THE S " I~ ING SHIP'S Rl:ruRtl IN THIS ISSU£ ~I>l~'" t-U : \ MILl!; WITHOUT COWS C

...... " , ~, .. "'''N... " sa...... _ ~p, .... ; ' . . ~ . ,~ ...... "" ~ _a <...... ' ...... , April 23, 1921 SCIENTIFIC AMERICAN 325

Right: Mixing vats and emulsors for maKing reconstructed milK

Milk Without Cows bel-obviated any objection from this angle. Special (Contin'tt(}(l !1'om 1,agc 325) bottle caps bearing the words, "Reconstructed Milk," By S. R. Winters or "Reconstructed Cream," revealecl the identity of the that the bottles coming from the machine MElCHANICAL dairy-affording an adequate milk product as well as the percentages of ingredients. could be conveyed by trucks directly into A supply to a city of :"5,000 population in the ab­ An equipment capable of handling 2,000 gallons of the milk room fol' storage. A galvanized­ .·ence of cows-is a commercial reality hitherto un­ bottled milk in an eight-hour day, with the opportunity iron tank· used for the washing of cans, heard of, a triumph emerging from war-created diffi­ of increasing the output to 3,000 gallons a day by the culties in Nitro, W. Va. It was the first commercial addition of another pasteurizing and emulSifying unit, which process was committed to hand la­ demonstration of the possibilities of producing fluid was agreed upon as adequate. Milk and cream could bor, together with a rin er and steamer, milk from a cowless dail'y in the United States. be dispensed in either bulk or bottled form, although was situated against the south wall of the I ha ten to explain the significance of the coined ample eq uipmen t was available for bottling the output. washing room. A brush washer, for phl'ase, "mechanical dairy," lest the reader ponder The milk-handling machinery con is ted of a buttermilk scrubbing extremely dirty containers was the question originally asked by the SCIE TITlC AMERI­ machine of 300 gallons capaCity; a milk pump; two 300- ) CAN when the subject was submitted in a skeletonIzed gallon ice-cream batch mixers; two centrifugal emul­ located on the north wall of the room, form, "Just what do you mean by this term?" ~'ech­ sors of 200 gallons capacity each, belt-driven from 2- A two-effect water still, with a capacity nically described as recon tructed milk, the product horsepower motors ; one tubular milk cooler of 5,000 of 350 gallons an hour, was stationed on is- made by the emulsification o f oliUerfat in- normal - pounds per llOur cApacity, compo ed of tWo sections, one for water and one for brine; an antifoam tank; a an elevated platform in the southwest skimmed milk. Reconstructed skimmed milk is ob­ corner of the washing compartment. The tainable either by diluting uusweetened condensed 01' rotary' bottle filler and capper; scales and tanks for evaporated skimmed milk with eli. tilled water or by di s­ weighing water, and scales for weighing butter; a effluent pipe from this still projected solving d.l'ied skimmed-milk powder in distilled water. porcelain topped table for cutting butter; and a Bab­ through the wall into the milk room and Skimmed-milk powder was used ill the Nitro manufac­ cock tester. All of the machinery, except the mixing di charged into a tin-lined distilled-water turing establishment as a source of solids not fat, and and pasteurizing vats, emulsors, butter scales, and >:torage tank of 1,0'00 gallons capacity. a first-rate quality of unsalted butter as a source of butter-cutting table, was located on the main floor. '£he butterfat. The percentage of fat. and solids not fat latter machines were on the balcony. The headroom The storage tank, being connected by a were proportioned in accordance with the different required to insure a gravity system from the mixing ' tin-covered piping to the suction end of products being manufactured. Reconstructed milk. vats to the bottle filler was not determined before the milk pump, at this juncture permit­ l'econstructed cr eam, ice-cream, and fermented milk construction of the building was begun, which fact ted the placing of a three-way valve, products, such as cultured buttermilk and cottage necessitated the elevation of the mixing vats two feet whereby the liquid could be drawn from cheese were produced by the war-created mechanica 1 above the floor of the balcony. They were supported on dairy. a stand made of 2-inch pipe, which arrangement should either the distilled water tank or the <, A liquid closely resembling milk and cream as the be avoided as it retards the speed of the machinery. buttermilk machine as desired, The dis­ result of emulsifying butterfat obtained from unsalted The sundry machines were connected with l1,6-inch charge from this pump al 0 facilitated butter in a solution of skimmed powder-milk 01' di­ milk piping, and the valves and fittings were of the the conveyance of the effluent either into luted evaporated skimmed milk had previously ap­ 'anitary type, easily cleaned. Overhead shafting was peared on the market. The procedure is popular with obviated. the various machines being operated by incli­ a weighing can on a platform near the the ice-cream industry, aud Army fielcl hospitals as vidual motors. As originally designed, the engineers 'kimmed-milk vat or to the mixing vats well as battleships have produced limited quantities did not contemplate the manufacture pf ice-cream but on the balcony. A field laboratory, lo­ of the fluid. '£hen, too, the National Dairy Show has the demands for the product were met by the installa­ cated in the dreSSing room, determined frequently exhibited this liquid as a method of ad­ tion of two can freezers, which supplanted a 60-quart the bacteriological content of milk and continuous brine freezer purcha ed but not put in vertising milk powders. Success in obtaining a satis­ its products as well as the acidity and fat factory product on a small s~a le was responsible for opera tion. These were placed in the balcony, and the assumption that operations of magnitude could be motor driven. Bottles were washed with an automatic ill milk A I5-ton refrigerating machine undertaken with reasonable expectations of obtaining jet washer, cleaning 4,000 bottles an hour. The preserved the milk as well as the cold- a liquid that would at least answer the emergency. pumps of the machine were set in motion by a direct­ torage department of the commissary. Dairy cattle were scatteringly distributed in this connected ]O-ho1' epower motor. The washer was lo­ The rooms were cooled directly by the ex­ mountainous region of 'West Virginia, a cow to the cated in the center of the room and was oriented so family obtaining rather than in immense herd. as are (Continued on page 33''i) pan ion of compressed ammonia, the com­ maintained in Wisconsin and the Middle pres or being propelled by a 30-horse­ West. Congestion of railway facilities power motor. Brine, cooled by the ex­ rendered uncertain the delivery of a po- pall 'ion of ammonia, was employed in tential source from the dairying communi- COOling the products of the mechanical ties of Ohio. In a word, a city of 25,000 inhabitants was without any visible milk dairy, the brine being circulated by a supply. '£he United States Public Health steam-driven pump. ", . . ervice shoulderecl the responsibility of The purest of water is essential in the devising ways and means of coping with making of recon tructed milk, the Nitro the unforseen contingency. The inviting water supply having been previously fil­ environments amid which the undertak- ing was launched are obvious-absence of tered and chlorinated. As with institu­ competition with the contents of the milk tions and men-the former being but the pail, assurance of a responsive market, shadows of grea t or small personalities­ and no violation of traditional health reconstructed milk in its finished form regulations. Yet it was with some trepi- cannot exceed the quality of the ingre­ dation that the procedure was authorized in view of the existing laws in the in- dients contained therein. The water terest of health which prohibit the modi- should be distilled; otherwise, mineral fication of natural food products. The 'alts may be conducive of harmful results known source and method of prepara­ to infants in partaking of the milk. The tion-unmistakably indicated on the la- hard waters of the ~1iddle West and those containing an ,excessive percentage of sulfate illustrate the point. The skimmed milk powder used at the I stant for 30 minutes. Inasmuch as the I Nitl·O manufacturing plant was dissolved butter has melted by the time tempera­ by a machine of 300 gallons capacity, the I ture attains 146 degrees, the pasteuriza-! unit being equipped with a revolving heat­ I tion of the skimmed-milk-butter mixture ing coil to which blades were attached, begins when tbe correct temperature is sen -ing the fnnctions of agitator and I r eached. Wbile at tbe pasteurizing de­ heater at the same time. The vat should I gree of beat, the fluid is conveyed be of cylindrical bottom, and should per­ through tbe centrifugal emulsors. Emul­ mit of no quarters for undissolved powder. sification is the r esult of forcing the mix­ The r equisite volume of distilled water ture through an extremely narrow open­ is poured into the vat and a weighed ratio ing, the centrifugal force being generated of powder added. A sugar scoop can be by revolving tbe bowl of tbe emulsor at used in removing the powder from the a r ate of 15,000 r evolutions a minute. banel into the vat. '.rhe coil agitator is From the emulsors the hot fluid or re­ in operation as the powder is being con­ constructed milk is conveyed to the up­ , ered to the vat, and the temperature per trough of the cooler through sections of the water while the powder is being of llh-inch sanitary mill,;: pipe to wbicb dissolved ranges from 70 to 80 degrees had been attached small conductor Fahrenheit. Having completed the dis­ heads. Foam multiples at this juncture, solving process, the skimmed milk is and to avoid its overflow at the edge of pumped to one of the mixing vats. H ere the conductor bead and trough, the instal­ prescribed quantities of butter, already lation of an antifoam tank between the parceled into 4-inch cubes on the porce­ emulsor and cooler is recommended by lain topped table are added and the mix­ the sanitary engineers. If the milk leaves ture brought to a temperature of 146 the cooler at a temperature of from 40 to degrees Fahrenheit where it remains con- 50 degrees Fahrenheit, one of the stan­ dard req uirements in the process of manu­ facture has been met. Proper regulation of the temperature as the milk departs from the cooler is essential; therefore, the flow of brine should be r egulated so that a minimum quantity of milk freezes to the cooler. An antifoam tank in the Nitro plant, the device bcing inser ted be­ twcen the cooler and the can and bottle fillers, eliminates the presence of air space between the cap and the surface of the milk when the bottles are filled di­ rectly from the cooler. The commonplace procedure of filling the containers with a rotary bottle filler is the succeeding proc­ ess, and having been capped with paper caps, the fini shed product is conveyed by motor trucks into the cold-storage room, subject to a temperature of 33 degrees Fahrenheit, until delivery is authorized. The reconstructed milk as manufac­ tured under war-created difficulties con­ tained 9 per cent milk solids not fat and 31h per cent butterfat. The cream con­ tained 25 per cent butterfat. Studies of the bacterial content of the output of the mechanical dairy indicate that it is satis­ factory from a health standpoint. Ice­ cream can be manufactured in quantity production with a bacterial content com­ paring favorably to that of well-pasteur­ ized milk and cream. Conclusious, care­ fully deduced from seasoned experiments, indicate that children can be nurtured on r econstructed milk as well as on nor­ mal cows' milk. Adult milk drinkers, used to drinking raw milk, will find the product somewhat distasteful, but those in the habit of partaking of pasteurized milk can switch to the newly-discovered fluid without observing an appreciable difference in flavor.