Bulletin No. 151

Special Products from Freshwater Fish

by A.W. LANTZ

Fisheries Research Board of Canada. Ottawa. 1966 SPECIAL PRODUCTS FROM

FRESHWATER FISH Bulletins of the Fisheries Research Board of Canada are designed to assess and interpret current knowledge in scientific fields pertinent to Canadian fisheries. Recent numbers in this series are listed at the back of this Bulletin.

Editor:

J. C. STEVENSON

Associate Editor: G. I. PRITCHARD Assistant Editor: R. H. WIGMORE

Production: R. L. MacIntyre

Fisheries Research Board of Canada Sir Charles Tupper Building Ottawa 8, Ontario, Canada

The Board also publishes the Journal of the Fisheries Research Board of Canada in annual volumes of monthly issues, and an Annual Report. Fisheries Research Board of Canada publications are for sale by the Queen's Printer, Ottawa. Remittances must be in advance, payable in Canadian funds to the order of the Receiver General of Canada. Publications may be consulted at Board establishments located at Ottawa; Nanaimo and Vancouver, B.C.; Sault Ste. Marie and London, Ont.; Ste. Anne de Bellevue and Grande-Riviere, Que.; St. Andrews, N.B.; Halifax and Dartmouth, N.S.; Ellerslie, P.E.I.; and St. John's, NOd. BULLETIN No. 151

Special products from freshwater fish

By A. W. Lantz

Fisheries Research Board of Canada Technological Unit, London, Ontario

FISHERIES RESEARCH BOARD OF CANADA

Ottawa, 1966 Smoked cisco and whitefish Smoked alewife and smelt

Pan-fried sausages Cocktail-style wieners

Smoked freshwater cod livers Variety of products © Crown Copyrights reserved

Available by mail from the Queen's Printer, Ottawa, and at the following Canadian Government bookshops :

OTTAWA Daly Building, Corner Mackenzie and Rideau

TORONTO Mackenzie Building, 36 Adelaide St. East

MONTREAL ..£terna-Vie Building, 1182 St. Catherine St. West

WINNIPEG

Mall Center Bldg., 499 Portage Avenue

VANCOUVER 657 Granville Street

or through your bookseller

A deposit copy of this publication is also available for reference in public libraries across Canada

Price $2.00 Catalogue No . Fs 94-1 51

Price subject to change without l10tice

ROGER DUHAMEL, F.R.S.C. Queen's Printer and Controller of Stationery Ottawa, Canada 1966

iv Contents

ABSTRACT, vii

INTRODUCTION,

COMPOSITION AND CHARACTERISTICS OF FRESHWATER FISH,

HANDLING AND DRESSING, 5

Handling, 5

Dressing, 5

BRINING AND SMOKING, 5

Cold- and hot-smoke techniques, 7

Brining, 7

Smoke generators, 10

Commercial-type smokehouses, 12

Home- or sportsman-style smokehouses, 16

CANNING, 17

SAUSAGE-MAKING, 19

Equipment, 20

Process, 21

WIENER-MAKING, 23

FREEZE-DRYING, 25

PACKAGING AND STORING, 25

Glazing, 25

Refrigerated storage chambers, 26

Package materials, 27

Cans, 28

STORAGE AND KEEPING QUALITIES OF PRODUCTS, 28

v Contents - Concluded

FORMULAS FOR PRODUCTS, 29 Formula 1. Dressed alewife: smoked, air-dried, and canned, 29 Formula 2. Dressed capelin: smoked, air-dried, and canned, 30 Formula 3. Dressed smelt: smoked, air-dried, and canned, 30 Formula 4. Dressed alewife: smoked, cooked in oil, and canned, 31 Formula 5. Alewife fillets: smoked, air-dried, and canned, 31 Formula 6. Chub fillets: smoked, air-dried, and canned, 32 Formula 7. Freshwater eel fillets: smoked, air-dried, and canned, 32

Formula 8. Freshwater cod livers: smoked and canned, 33 Formula 9. Freshwater fish: canned steak-style, 33 Formula to. Fishballs (servies) from freshwater fish, 34 Formula 11. White sauce for canned fishballs (servies), 34 Formula 12. Canned fishballs (servies) in white sauce, 35 Formula 13. Baked beans (for fishballs with beans), 35 Formula 14. Canned fishballs with beans, 36 Formula 15. Freshwater fish sausages, 36 Formula 16. Hot smoking of dressed freshwater fish, 37 Formula 17. Freshwater fish wieners, 37 Formula 18. Sweet-and-sour sauce (for wieners canned in sweet-and-sour sauce), 38 Formula 19. Freshwater fish wieners canned in brine, 38 Formula 20. Freshwater fish wieners canned in sweet-and-sour sauce, 39

ACKNOWLEDGMENTS, 39

BIBLIOGRAPHY, 40

vi ABSTRACT

Some of the characteristics of freshwater fish which affect methods of processing are described as well as types of processing, the equipment used or designed, and the techniques developed.

Many freshwater species known to the industry as "coarse fish" are not market­ able and represent a tremendous waste as potential food. Formulas have been developed to utilize species such as alewife, smelt, chub, burbot, sucker, inconnu, bullhead, carp, sheepshead, and others. Sausages, wieners, fishballs, and canned and smoked products have been produced, as well as combinations of several of these processings, for example: dressed alewife smoked, air-dried, and canned; fish wieners canned in sauce; and burbot livers brined, smoked, and canned. Storage and shelf life of special products is discussed and various packaging materials are described.

Research in the field of fish-product development cannot be considered complete, but sufficient progress has been made for industrial application of the information contained in this Bulletin.

vii INTRODUCTION No country, with the possible exception of Japan, has realized the potential of its fishery resources through the production of variety products. In 1962, the Japanese fish-sausage industry alone was worth 91 million dollars (Ueno, 1963). There is a growing interest in special products from both marine and freshwater fish flesh in the United States. Sausages made entirely from tuna flesh have been marketed for some time under such trade names as "Friday Franks" (Anon., 1950) and "Tuna-links" (Anon., 1961) and some commercial corporations carry out extensive research to develop fish products which could be considered counter­ parts of products made from farm animal meats. An awareness of the potential commercial value of fish sausages is also evident in the Netherlands (Schoonens, 1950), in Germany (Reuter, 1949), and in Australia (Montgomery and Prater, 1963; Prater and Montgomery, 1963). In Canada, experimental processings of products in which fish was the basic ingredient have been reported from time to time (Lantz, 1947, 1948a, b, 1949, 1961 b, 1962, 1963; Sidaway, 1944, 1945; Sunderland, 1938, 1939, 1940). Fish wieners and bologna were made experimentally in Canada in 1944 (Lantz, 1945). Millions of pounds of freshwater fish are produced annually in Canada; in 1962, landings of freshwater fish from Ontario, Manitoba, Saskatchewan, and Alberta totalled 123,909,000 Ib, valued at $11,761,400 (Dominion Bureau of Statistics, 1964a, b, c, d). Many of the fish caught, however, do not find a ready market; with the development of new products from the unwanted fish, it is hoped that some of the problems which plague the commercial freshwater fisheries will be solved. Since trawl nets were introduced to Lake Erie (Lantz, 196 1a), the increased catch of smelt (Osmerus mordax) has included a proportionate increase of fish too small for the dressed fish trade. Thousands of pounds of undersized smelt are discarded, and a valuable food resource is wasted. Other problems include the annual die-off and consequent loss of tons of alewife (Alosa pseudoharengus) and losses of valuable fish species due to the effects of predatory sea lamprey (Petro­ myzon marinus). To help overcome these and other problems, and to bolster the economy of the Canadian freshwater fishing industry,inv estigations were undertaken to develop methods to better utilize available fish species. The processes by which products have been developed are described in this Bulletin.

COMPOSITION AND CHARACTERISTICS OF FRESHWATER FISH Flesh of the various species of freshwater fish differs in physical character­ istics and in quantity of constituent composition, particularly fat. Chemical analyses of freshwater fish (Schmidt, 1948; Dugal, 1962) have shown that there are quanti­ tative differences in constituents of flesh from the same species of fish (Table I). Canning of freshwater fish presented a texture problem. An unpredictable over-soft texture of some canned freshwater fish appeared to be related to the quantity of free liquid released from the flesh during the sterilization process. The amount of liquid differed in cans from the same processing. Various methods of extracting liquid from the flesh prior to sterilization have been tested and are described in the section on Canning. The problem of excess moisture, and mushy or over-soft flesh has been en­ countered elsewhere. At the Torry Research Station, Aberdeen, Scotland, fish were dipped in powdered carboxy-methyl cellulose prior to canning. This was claimed to improve the appearance of the pack (Dept. of Scientific and Industrial Research, 1959).

TABLE 1. Composition of fillets from several species of fish caught in various Canadian lakes.a

Skin on or Species and source skinless Moisture Protein Ash Fat

Alewife (Alosa pseudoharengus) Lake Erie skin on 60 22 Bass, rock (Ambloplites rupestrisl Lake Huron skin on 79 19 Bass, white (Lepibema chrysops) Lake Erie skin on 75 18 3 5 Lake Huron skin on 75 20 1 4 Bowfin (Amia calva) Lake Erie skinless 79 18 2 Carp (Cyprinus carpio) Lake Huron skin on 76 19 5 Catfish (Ictalurus lacustris) Lake Erie skin on 74 16 9 Lake Huron skin on 72 16 11 Chub (Leucichthys sp). Lake Huron skin on 71 16 2 13 Cod, freshwater (Lata lota)b Lake Erie skin on 80 17 2 Lake Huron skin on 80 19 1 Upper Rideau Lake skinless 82 17 Herring, lake (Leucichthys sp.) Lake Huron skin on 72 21 2 6 Inconnu (Stenodus leucichthysl Great Slave Lake skinless 77 18 5

(Cant inued)

2 TABLE I. Composition of fillets from several species of fish caught in various Canadian lakes.& (Concluded)

Skin on or Species and source skinless Moisture Protein Ash Fat

Mullet (Moxostoma rubreques) Lac La Ronge skinless 80 17 2 3 Perch, yellow (Perea flaveseens) Lake Erie skin on 78 17 3 Lake Huron skin on 78 20 1 Pickerel, yellow (Stizostedion vitreum) Lac La Ronge skinless 79 18 3 Pi ke, Northern (Esox lucius)C Great Slave Lake skinless 81 18 Snake Lake (Sask.) skinless 79 19 2 Shad, gizzard (Dorosoma eepedianum) Lake Huron skin on 66 16 15 Sheepshead (Aplodinotus grunniens)d Lake Erie skin on 76 18 6 Lake Huron skin on 74 17 8 Sturgeon (Acipellser /ulveseens) Lake Huron skin on 70 16 12 Sucker, common white (Catostomus eommersoni) Lake Erie skin on 76 16 4 3 Lake Huron skin on 78 18 2 2 Lesser Slave Lake skinless 80 16 3

Sucker, longnose (Catostomus eatostomus) e Lesser Slave Lake skinless 79 16 4 Trout, lake (Cristivomer namayeush) Great Slave Lake skinless 79 17 4 Tullibee (Leuciehthys tullibee) Snake Lake (Sask.) skinless 82 16 2 Whitefish, lake (Coregonus clupea/ormis) Cedar Lake (Man.) skinless 77 19 4 Great Slave Lake skinless 71 16 14 Snake Lake (Sask.) skinless 79 17 3 Lake Huron skin on 66 17 16 Lake Superior skin on 77 19 3 Lake Winnipeg skinless 73 17 10 Pipestone Lake (Sask.) skinless 79 17 2

&Information in this Table originated from data in Fish. Res. Bd. Canada, Vancouver In d. Mem. No. 9, 12, and 13; and London BioI. Sta. and Tech. Un it Circ. No . 5. b Also known as burbot, ling, or maria. C Also known as jackfish. dAlso known as drum, sunfish, or grunter. e Also known as red sucker.

3 The application of vacuum as pretreatment for canning some types of fish with initial moisture content of about 75% appeared to have important advantages (Harrison and Roach, 1952).

In sausage products, moisture-blending properties varied with each species. Flesh from sheepshead (Aplodinotus grunniens) and from carp (Cyprinus carpio) had good adhesive properties which blended well with other fish flesh, or could be used as a single basic ingredient. Smelt flesh lacked cohesiveness and had to be blended with other flesh to achieve a firm product. When minced, smelt flesh developed an unattractive dark grey color quite unlike the natural color of the flesh. Cooking the flesh before mincing reduced discoloration of the mince but this procedure was considered unsatisfactory. Other methods for utilizing smelt were considered more economical and a number of these are described.

Nutritive values of fish products described have not been determined because a paper on the subject has already been published (Tarr, 1960).

After the formula for wiener products had been standardized, a study was made of the stages in development of the meat emulsion. Slices of emulsion 10 JL thick were prepared on slides, dyed, and examined under the microscope (Fig. 1). The fish flesh comminuted and homogenized in a mill specially designed to reduce

FIG. 1. Microscopic slides (X90) showing: (a) comminuted common white sucker flesh, (b) same as (a) with salt added and blended, (c) same as (b) with ice added and blended, and Cd) same as Cc) with fat added and blended.

4 bone particles to undetectable size is shown. It has been impossible, to this time, to stain the minute bone particles so they could be distinguished in the emulsion. It appeared that the addition of salt brought about solubilization of the protein. The same mixture after the addition of ice, and the mixture after the addition of hydrogenated vegetable fat, is shown. These sequence slides illustrate some changes which occur during the mixing procedure.

HANDLING AND DRESSING HANDLING Fish for any type of processing must be fresh, and should be kept fresh by sanitary handling, processing, and storing techniques, and by keeping the product as cold as possible at all times. These methods will help control the activity of enzymes and bacteria and thus retard spoilage. As soon as fish are lifted from the lake or river, they should be placed in a clean container and maintained at 32 F (Young, 1938; Castell, 1954). Fish are fragile and have soft flesh which bruises easily. Bruising accelerates deterioration ancl any abrasion or rupturing of the skin permits spoilage bacteria to penetrate the flesh. It is extremely important that fish be gutted soon after catching. Fish should be thoroughly washed before and after gutting to remove any residual digestive enzymes and bacteria (Tarr and Lantz, 1949).

DRESSING Dressing fish includes removal of the scales (scaling) and the gut. Fish should be taken from the chilling medium, washed, and placed on a clean table or cutting board close to a supply of clean, cold, running water. Equipment for scaling and washing fishhas been in use for some time (Fisheries Research Board of Canada, 1949, 1955); the gutting and washing operation has more recently been mechanized (Chivilenko and Vedernikov, 1960). For larger species of fish these processes must still be done by hand (Lantz, 1964a), preferably in a processing area similar to the one illustrated in Fig. 2.

BRINING AND SMOKING Assessment of the potentials of freshwater fish for smoking involved experi­ mental processings of various species of fish from numerous freshwater lakes of Alberta, Saskatchewan, Manitoba, Ontario, and the Northwest Territories.

Buffalo fish (Megastomatobus cyprinella), goldeye (Hiodon aloso ides) , lake trout (Salvelinus namaycush) , burbot (freshwater cod, maria, ling) (Lota Iota), northern pike (jack fish) (Esox lucius), pickerel (pike-perch) (Stizostedion vitreum), mullet (redhorse) (Moxostoma aureolum), tullibee (Leucichthys sp.), and whitefish (Coregonus clupeaformis) were smoked by the cold-smoke process and reported by Lantz (l948b).

5 FILLE TER

I

SLOPE 2" in 10'

--=---GRATED SCREEN OR WIRE MESH CONVEYOR

SACKER a

WEIGH SCALE z----INTERCEPTOR � TANK

-10 FREE"ZER

COOKER GRiNDER

Flo. 2. A practical setup for processing fish.

More recently, whitefish, chub (Leucichthys sp.), common white sucker (Catostomus commersoni), pickerel, goldeye, carp (Cyprinus carpio), lake trout, alewife (Alosa pseudoharengus), smelt (Osmerus mordax), common eel (Anguilla rostrata), and sea lamprey (Petromyzon mar in us) have been smoke-treated by the hot-smoke method.

The hot-smoke method was used also as a preliminary to canning alewife, capelin (Mallotus villosus)/ and smelt in sardine-type packs. These species have an excellent potential as canned, smoked, sardine-type products. Smoked eel fillets were satisfactory for canning. Lamprey could not be filleted because of the notochord spinal structure, but it was possible to cut the lamprey into sections for smoking prior to canning.

Market potentials for smoked freshwater fish appear to be good to excellent for all species tried except buffalo fish which had a poor appearance and gelatinous surface texture. A very limited market could be anticipated for canned smoked lamprey. In general, freshwater fish, particularly those with an appreciable fat content, absorb smoke evenly and develop good flavor characteristics and can, therefore, be considered suitable for smoke treatment by either hot- or cold-smoke techniques. Cold-smoke-treated products have a limited shelf life, approximately

lPrevalent in coastal waters of Hudson Bay.

6 the same as fresh fish, due to the mild smoke and low-temperature treatment. The hot-smoked product has a measure of preservation but this does not obviate the necessity for low-temperature storage.

COLD- AND HOT-SMOKE TECHNIQUES Smoked fish products are produced by a combination of brining, drying, and smoking. The two conventional types of smoke treatment are known to the industry as "cold-smoke" and "hot-smoke." The primary difference in the two techniques is one of temperature range. For cold-smoking, the brine-dipped, dressed fish or fish fillets are smoke-treated in conventional smoke tunnels at temperatures between 70 and 90 F. This cold-smoke process imparts a mild or light smoke flavor but any degree of preservation is dependent upon the length of time the fish are in the smoke chamber. For appreciably extended preservation, the treatment would have to be prolonged up to 2 or 3 weeks.

The hot-smoke technique has been used for most of the products described. Hot-smoki.ng involves starting smoke treatment of dressed fish or fish fillets at a temperature of 120 F and gradually increasing the temperature to 180 F at 10- or IS-min intervals over a 3-hr smoke period. Both time intervals and temperature rises are somewhat dependent upon the species of fish being treated and the size or weight of the fish. This type of smoke treatment should not be confused with barbecuing which differs from the method described here. For barbecuing, the fish are placed in close proximity to the smoke-producing fire. Both the hot-smoke treatment and barbecuing arrest deterioration temporarily because the fish are partially or completely cooked and the enzymes which cause autolysis are destroyed. The advantages of hot-smoke treatment are generally conceded to be the develop­ ment of desirable flavor and sheen rather than any appreciable improvement in preservation. All smoked products require careful handling and storage controls.

BRINING For smoke treatment by hot- or cold-smoke methods, the fish should be firm-textured, of top quality, and thoroughly washed before brining, which is preliminary to smoking. Brine immersion has been credited with bringing about a physical improvement in both texture and appearance of fish fillets.

Usually, the dressed fish or fillets prepared for smoking are immersed in a strong (80 sal) brine solution for short periods of time. A brine solution of 80 sal may be defined as a solution 80% saturated with sodium chloride. A saturated brine solution (100 sal) is prepared and diluted to various strength brines as required.

Brine solutions of any desired strength can be made by dilution of saturated brine with water at 60 F (Table II). All brine solutions should be stirred before and after dilution to ensure uniform distribution of salt; temperature of solution

7 must be maintained at 60 F. A special type of glass hydrometer, known as a salino­ meter (or salimeter), should be used to assure correct brine strengths. When a hydrometer is floated in brine, the salinometer scale is read at the brine surface. Salinometers are inexpensive and are available at most hardware stores.

TABLE II. Saturated (100 salinometer) brine dilution table at 60 F.

Partsa saturated Partsa Sal brine brine water strength

19 5b

9 10

4 20

3 25

50

3 75

4 80c

9 90

19 95

aExample: one cup standard measure. bStrength of brine used for canned wieners in brine. CStrength of brine used for brining dressed fish and fillets prior to smoking.

Saturated brine can be produced by a simple apparatus which can be built very inexpensively. The equipment was devised to produce 10-15 gal of saturated brine per day (Fig. 3). It includes an open-top plastic pail fitted near the bottom with a drain cock; a small Pyrex or cereal bowl, which is placed in inverted posi­ tion ont inch of crushed pebbles placed on the bottom of the pail; a piece of rubber tubing which is attached at one end to the drain cock and laid on top of the pebbles with the other end placed halfway under the inverted bowl. Crushed washed pebbles are added to completely cover the top of the bowl to a depth of } inch, then on top of the pebbles clean coarse sand to a depth of 1 inch is added and topped with coarse salt up to the three-quarter-full line on the pail. When the apparatus is ready, water is allowed to trickle onto the salt through a regulating float valve located above the pail. (Suitable valves and floats are obtainable from plumbing suppliers.) After 30 min, the outlet spigot is opened and adjusted so that one drop of saturated brine falls every second into a plastic container placed di-

8 recdy below the spigot. Saturated (100 sal) brine contains 3 Ib 2i oz of salt to each Imperial gallon of water. Any brine not required for immediate needs should be stored at 60 F in a plastic container coveted with a tight-fitting lid.

FLOAT VALVE

SALT -",-�-

CRUSHED ROCK

COLLECTING CHAMBER FOR SATURATED BRINE

FIG. 3. Brine maker.

Small fish and fillets take up salt faster than large fish and dressed fish, so brining times must be determined by strength of brine being used to treat the fish and by weight of the fish being treated. Before treatment, all fish for brining and smoking should be weighed and sorted into groups of comparable weight. Tables III and IV may be used as guides for brining dressed fish and fillets before smoking. The operator will soon determine, through experience, the length of time the fish should be brined to provide the desired end product.

TABLE III. Time required for brining dressed fish of varying weights in 80 sal brine.

Approximate Brining weight time Species (oz) (min)

Pickerel, yellow (Stizostedion vitreum) 25 10 Pike, northern (Esox lucius)"' 40 15 Trout, lake (Cristivomer namaycush) 40 15 Tullibee (Leucichthys sp.) 20 8 Whitefish,lake (Coregonus c/upeajormis) 25 10

a Also known as jackfish.

9 TABLE IV. Time required for brining fish fillets of varying weights in 80 sal brine.

Type Approximate Brining of weight time Species fillet (oz) (min)

Mullet (Moxostoma rubreques) butterfly 40 15 Mullet (Moxostoma rubreques) single 8 5 Pickerel, yellow (Stizostedion vitreum) single 12 10 Pike, northern (Esox lucius)& single 20 16 Trout, lake (Cristivomer namaycush) single 12 12 Tullibee (Leucichthys sp.) single 12 12 Whitefish, lake (Coregonus clupea!ormis) single 12 10

& Also known as jackfish.

SMOKE GENERATORS

Smoke generators available to the industry vary from the traditional open­ hearth types, which burn either damp hardwood sawdust or utilize a smoldering pile of sawdust at the bottom of a smoke kiln, to a sawdust fluidizer-reactor.

FIG. 4. Sectional drawing illustrates directional flow of smoke in the Paul Wiencke, Jr. H. O. smoke generator supplied by Ma-Tro-fa Agenturer A/S, Oslo, Norway. "A" Air (intake regulated) passes down through the electric hot elements "B" to support partial combustion of the ignited wood chips "e" to form smoke. "D" Forced controlled air from injection pipe creates partial va,cuum in the interior area of the combustion wheel "E," causing smoke to be drawn through slots "F" and mix with air from the injection pipe. The conditioned air and smoke is then directed through duct "G" to the smoke tunnel.

10 One of the newer commercial smoke generators consists of a wheel containing twelve small combustion chambers. As the wheel slowly revolves (! rpm), hard­ wood chips are gravity-fed into each of the twelve individual combustion chambers. The chips are ignited automatically at the top of the circumference (adjacent to the gravity-feed opening) and before a half revolution of the wheel has been com­ pleted the chips are completely carbonized. Aromatic substances are drawn with the smoke through grating slots at the base of each chamber into a space which surrounds the hub of the multi-combustion-chamber wheel (Fig. 4) and from there into the smoke tunnel. Another of the recently-developed smoke generators is a friction smoke generator described by Weir et al. (1961). Smoke in this system is produced by pressing the end grain of a hardwood block against a rotating carbide-tipped disk (Fig. 5).

TO SHOIf£' TI/KNEI.

rILTERBE�

"" , " , " , � '� ',.

DISK "",TH CARBIIJE I BLADE� \: I I

FIG. 5. Drawing of a friction smoke generator <:supplier : L. C. Spiehs Company, Chicago, Illinois).

11 A third type of smoke generator has been developed which produces smoke from a fluidized bed of sawdust in a stream of hot air (Nicol, 1960). At time of writing, this smoke generator was not available for commercial use.

COMMERCIAL-TYPE SMOKEHOUSES

Smokehouses or kilns vary from the box-type tunnel of the last century to the complex insulated kilns into which controlled amounts of air-conditioned smoke are fed. Various types of tunnels have been developed in this century, notable among them the tunnel at the Fisheries Research Board of Canada Techno­ logical Laboratory, Halifax (Fig. 6), reported by Linton and Wood (1943); the Torry Research Station's controlled-smoke kiln (Cutting, 1948) (Fig. 7); and the horizontal air-conditioned tunnel developed at the Fisheries Research Board of Canada Technological Laboratory, Vancouver (Sid away and Young, 1943). To improve operation of the tunnel, modifications were made (Lantz and Young,

FIG. 6. Smoke tunnel developed at the Fisheries Research Board of Canada Technological Research Laboratory, Halifax, N.S.

12 S,,",Ol<;E <;;ENER"',oq +-f-p

_�H.�:':':'.O·�'I�.===== 14·-O,,-======�.��2::::"�O�·.j I-1 21'-9"- U

FIG. 7. Side elevation of the smoke tunnel designed at the Torry Research Station, Aberdeen, Scotland. T ., \"!

, co/'{YEYOR , , , "'L ...... J·, I I , , , � � �t. "'''". ",�· ..jt I ,r TAAY WITH A I I SP£Et:J Or 9 /""G'crPEPt MIIY. I L04D: 100 pOl/NDS OF FISH PIER fRAY , I I ,

,sPRAY II Z%LES

SMa €L€r:AVON E8Q

FIG. 8. Elevation drawings of the vertical conveyor tunnel designed for the Prince Rupert, B.C. Fishermen's Cooperative.

1949). The principles of the modified laboratory tunnel were applied in the design of a vertical commercial tunnel built by the Prince Rupert Fishermen's Cooperative Association (Lantz, 1949) (Fig. 8).

13 A laboratory-size replica of the vertical commercial tunnel has been used in a variety of applications for investigating the smoke-treatment potentials of freshwater fish. The application of smoke to small species of freshwater fish pre­ sented problems which led to a modified design of this new tunnel which combines continuous smoke treatment with an automatic turning feature (Fig. 9).

t

- � PRODUCT RELEASED FROM I3ASKET

FIG. 9. Continuous conveyor and baskets fo r smoking fish.

When fish were placed on the open screen trays of the original vertical tunnel for smoke treatment, the screens left undesirable indentations on the surface of the fish. When fish were hung by the tails from hooks, the operation was time­ consuming and labor costs on a commercial project would be too high. Also, a number of fish dropped to the bottom of the tunnel as the smoke treatment partially cooked them. Hexagonal baskets, mounte� on a qual-chain conveyor, hold the fishas the baskets are moved up and down on a series of vertical elevations and vertical dips along the conveyor system. The fish are turned by gravity as the baskets turn on the up-and-down curves of the dual-chain conveyor. Smoking time can be regulated by controlling the speed at which the baskets and conveyor travel. One operator is required to load the baskets which are emptied automatically

14 as each basket turns at the lowest corner of the tunnel opposite the loading area. The baskets then pass through a cleaning solution in a trough along the bottom of the tunnel before entering the loading zone for reloading.

It was not possible to construct a laboratory-size tunnel; however, it was possible to examine the effect of automatic product-turning during smoke treat­ ment. Completely closed baskets were constructed and mounted on the outside of the conveyor chain in the air-conditioned vertical tunnel as illustrated in Fig. 10.

SMOI(K ER

WIRE MESH BASKET �WITH PRODUCT

FIG. 10. Laboratory vertical smoke tunnel showing a token number of cylindrical wire baskets fastened to the exterior of the conveyor chain.

Enclosed mesh baskets with hinged lids are necessary because these baskets make a complete turn with every cycle of the tunnel's conveyor. It is evident from the illustration that similar adaptations can be made to any vertical or horizontal conveyor tunnel for smoke-processing batch lots of fish. It should be pointed out that tunnel capacity is predicated by the number of baskets that can be installed conveniently on the conveyor chains.

The revolving basket system was found to be very effective and produced a superior product, as shown by comparison of results of the three techniques (Fig. 12). The three lots of smelt shown in the photograph were given identical smoke treatment but one lot was suspended by the tail; the second lot was laid on the open screen trays with the cavity opening on the downward slope of the screen to permit drainage of free liquid from the cavity; and the third lot was placed in the enclosed baskets so that the fish revolved on the turns. The smelt that were

15 hung by the tail had good color, were uniformly smoked, and had no free water in the cavity, but losses from dropping during processing were appreciable. The smelt on the open screen trays had a tendency to stick to the screen mesh despite frequent manual turning end over end during treatment; fish appeared over­ dried at the cavity opening and showed screen markings on the skin. Smelt from the revolving baskets were evenly colored and uniformly smoked, had a smooth pliable skin, and naturally rounded body contour with no free water in the body cavities.

HOME- OR SPORTSMAN-STYLE SMOKEHOUSES Requests for a smokehouse suitable for smoke-processing fish in rural areas initiated the construction of a galvanized sheet-metal smokehouse (Lantz, 1964b) (Fig. 11). This smokehouse is useful for teaching and demonstration purposes.

I \tI

FIG. 11. Galvanized sheet-meml smoke tunnel. Description and dimensions were described by Lantz (1964b) .

16 FIG. 12. Lot 1. Smelt suspended by the tail from hooks during smoke treatment; Lot 2. Smelt smoked on screen trays; and Lot 3. Smelt smoke- treated in rotating baskets. All fish were from the same catch. � ��UBE � SERT � J 'LJ- SLIP JOINT O � II I DIA. t,J TUBING

FRESH AIR DAMPER (Mix with smoke at A)

AIR DAMPER FOR SAWDUST COMBUSTION

FIG. 13. Framework of portable smoke tunnel designed for sports fishermen's use.

More recently, a collapsible tunnel, which is transportable and readily assem­ bled by hand, has been designed at the request of sports fishermen who want a simple apparatus for smoking fish in remote areas (Fig. 13 and 14).

CANNING In 1948, a steak-style pack of whitefish was canned as an experiment for a company operating in the Northwest Territories. Testing laboratories in Chicago made taste tests on the p�oduct for the fishing company and the results indicated a good market potential for canned whitefish if it could be supplied in quantity.

In 1960, the same company considered production of canned fish and re­ quested further tests into canning potentials. These investigations were under­ taken by us and the formula developed for steak-style packs of whitefish, suckers, inconnu (Stenodus leucichthys), chub, and other species is presented on page 13.

17 FIG. 14. Photograph shows fireproof Fiberglas cover which encloses portable smoke tunnel during smoking operation.

It was not possible to obtain fresh whitefish for the canning experiments, so 1150 lb of frozen whitefish fillets were obtained from Prairie lakes. Full details of capture, filleting, freezing, and shipping were included and provided an op­ portunity to combine canning experiments with an evaluation of storage tem pera­ tures and length of storage intervals in relation to quality. After immediately canning 240 Ib for use as controls, equal lots of the re­ maining frozen whitefish fillets were stored at 0, -10, and -30 F. Thereafter, sam­ ple lots from each storage temperature were canned at 3-month intervals, over a IS-month period, using exactly the same technique for each lot. Sixteen lots of the canned whitefish were sent to two of the Fish InspeCtion Laboratories of the Department of Fisheries for taste tests. The purpose of this testing by impartial tasters was twofold; to determine when perceptible deteri­ oration occurred at each of the three storage temperatures and to decide if soft texture in some canned whitefish could be related to deterioration changes. It was possible to estimate the canning potential of whitefish held in storage at the three temperatures. From the results of the organoleptic tests it appeared that differences in storage temperatures had a much greater effect upon quality

18 than did differences in storage time. Judging on the basis of color, odor, and flavor, it was concluded that whitefish stored at a temperature of 0 F had a maximum storage potential of 7 months; at a temperature of -10 F, a maximum storage potential of 1O! months; and at a temperature of -30 F, a storage potential of 16 months. All species of freshwater fish canned by previously established techniques presented a texture problem related to the release of free liquid from the flesh during the sterilization process. The texture problem was less pronounced with whitefish than with other species but when it did occur in canned products, soft texture could not be related to deterioration changes. Modifications to canning techniques were necessary to reduce the quantity of free liquid and achieve a uni­ formly firm texture in the canned fish. Modifications to technique which were tried included cooking the packed product by inverting the cans in a steam bath for varying periods of time at various temperatures; vacuum exhausting the cans at 27 inches for various times up to 20 min; blanching dressed fish for periods up to 5 min in boiling sodium chloride solutions of strengths from 60 sal to saturated brine (100 sal); cooking dressed fish in hot corn oil before packing; and partial dehydration of fish in the air-conditioned tunnel before packing into cans. In evaluating the effect of the various canning modifications which were tried, some justifiable conclusions can be postulated. All factors being equal, high-temperature cooking in an invert position was more effectivethan high vacuum (27 inches for 20 min) for extracting excess moisture while retaining other desirable characteristics. Blanching had no effect upon the amount of free liquid in sterilized products. Cooking in oil reduced the free liquid but the appearance of the product was marred by ruptures in the skin of the fish. Partial drying in the air-conditioned tunnel for 75 min, or to a weight loss of 20%, at graduated temperatures from 130 F rising to 170 F by the end of drying time, completely eliminated free liquid in the cans and produced a product satisfactory in appearance. Alewife, capelin, and smelt have been canned after drying, and after a com­ bined drying and mild-smoke treatment at temperatures between 130 and 170 F for 75 min. These products compared very favorably with imported and domestic sardine packs currently available on Canadian markets.

SAUSAGE - MAKING Sausages are made from seasoned minced meat enclosed in natural or syn­ thetic casing; they may be fresh or cured. The meat sausage, in one form or another, dates back through the centuries and appears to have been one of the early forms of processed food; records show that it has been produced commercially since the Middle Ages. Methods of preparation varied according to climatic conditions within the country of origin. Dried and semi-dried comminuted meat sausages originated in warm climates where the highly spiced varieties became very popular.

19 Fresh and lightly-smoked were developed in the temperate zone where highly spiced varieties have recently been introduced. The popularity of meat- sausage products has not diminished over the years and seems unlikely to do so; it is possible that fresh and smoked fish sausages will some day enjoy the same popularity.

Techniques which are used the meat industry to produce meat sausages were applied and evaluated in the of fish sausages.

EQUIPMENT

Two pieces of equipment used in production of meat sausages are essential for preparing satisfactory fish sausages: a food cutter for cutting and blending in­ gredients and a stuffer for extruding the mixtures into casing. A newer develop­ ment in processing equipment is a cutting mill which makes it possible to utilize fish bones and skin in such a way that neither is detectable in the finished product. All are available commercially.

The food cutter (sometimes referred to as a "silent cutter") is used for cutting, chopping, and comminuting fish flesh, and for blending fish-sausage mixes. The food cutter consists of two blades, electrically operated, which rotate vertically at 1750 rpm in the centre-back of a bowl at the same time, rotates horizon­ tally (Fig. 15).

FIG. 15. Fish-meat mixture in food cutter manufactured by Hobart Mfg. Co. Ltd., Toronto.

20 FIG. 16. Operators extruding fish mixture into sausage casing from an F. Dick stuffing machine supplied by Lamplough & Co., Montreal.

The stuffer (Fig. 16) consists of a cylinder from which the fish mixture is extruded through a horn into casing. The cutting mill (Fig. 17) reduces flesh, skin, and bones of fish to a smooth homogenized mass which is very satisfactory as the basic ingredient for sausages and other comminuted fishproducts. Centrifugal action forces the fish fleshbetween knife blades stacked to form a head (Fig. 18). Spacing between the blades determines fineness of the particles. Cutting heads are available for producing fine- and coarse­ textured minces.

PROCESS Sausages were prepared from the flesh of whitefish, carp, smelt, sheepshead, chub, and suckers. In each case the fish flesh was comminuted, seasoned, blended, and extruded into natural (sheep) casing and linked by hand to form sausages. Fish fillets in three different forms were used: fresh (unfrozen), frozen and fully thawed, and frozen and partially thawed. These were placed in the food cutter and minced. To the fresh and fully thawed fish, ! Ib of ice per 5 lb of fish was added to keep the temperature at 35 F. Fat, in the form of hydrogenated vegetable shortening, was added and a smooth-textured mixture developed during blending. One pound of shortening to 5 lb of fish flesh yielded the characteristics considered desirable in the finished sausage product. Fish protein tolerance for fat was somewhat higher than the amount used but too much fat brought about a breakdown in the emulsion and the mixture lacked the firmness necessary for

21 FIG. 17. Food cutting mill manufactured by Urschel Laboratories, Inc., Valparaiso, Indiana. efficient handling. Spices were mixed with the salt and added at the beginning of the operation to improve flavor permeation. Ginger, sugar, and white pepper were selected as seasoning and frozen onion flakes were used for flavor. Onion flakes were used in the frozen form for convenience and to help maintain the mix at a low temperature. Ginger was selected because it had a rich fragrance and clean hot taste which left no aftertaste. Sugar was added for its flavor­ enhancing property. Empirical tests were made to determine the effectiveness of various binders. Dry-milk solids, powdered egg, bread crumbs, cereal, and a commercial prepa­ ration were tested. There was no evidence that a binder was required for develop­ ment of desirable texture in fresh sausage. A small quantity of dried bread crumbs had a tenderizing effect and imparted a plumpness which was retained in the cooked product; however, it could not be concluded that bread crumbs were necessary for satisfactory texture in products made from an ingredient as naturally tender and moist as fish flesh.

22 PRODUCT TO BE CUT

HORIZONTAL CUTTING ED GE

VERTI CAL CUTTING EDGE

IMPELLER (ROTATING)

CUTTING HEAD (STATIONARY)

CU T PRODUCT

FIG. 18. Cutaway of cutting head and impeller on cutting mill.

Small-quantity formulas were found to be more reliable than those involving large quantities of ingredients. Large-batch formulas can be standardized by starting with a small batch and increasing it, by stages, in multiples of not more than four. Appearance, texture, and flavor of each succeeding increase should be recorded and tested against the results of the original formula, until the desired results are obtained. A basic formula for preparation of fish sausages appears on page 36.

WIENER - MAKING

Fish flesh suitable for fresh sausage products was equally satisfactory for wieners. Bullhead (Ameiurus nebulosus) , whitefish, sheepshead, carp, bullhead blended with carp and sheepshead, chub with whitefish, chub with suckers, and suckers with carp have been used as the basic ingredient for smoke-cured sausage products (wieners).

A binder, which was not necessary for fresh sausages, was required for wieners, to provide the greater density necessary to retain shape in the finished product. Commercial binders have the advantage of uniform consistency and quality, but milk powder, egg powder, or cereal binders may also be used.

23 Dressed fish and fillets were processed separately in the cutting mill. Homo­ genized comminuted fish with bones utilized 65-70% of the total weight of the fish, and fillets utilized 47-50%. Fish in both forms were blended with a salt­ spice mixture in the food cutter. The spice mixture was prepared commercially to our specifications (page 37).

Fish flesh had a limited tolerance for moisture and fat. This was atTected by the sequence in which moisture (ice) and fat (hydrogenated shortening) were added and also by the temperature of ingredients during .cutting and blending operations. Without stopping the machine, ice was added first and blended into the fish-flesh mixture, then the shortening was added.

Binder was added next and blended, and finally bread crumbs were added. Government regulations limit the amount of filler, fishbinder, and other ingredients to that represented by 4% reducing sugars calculated as dextrose, with moisture permitted to 70% (Dept. of National Health and Welfare, 1964).

The blended fish mixture was packed into the stutTer, extruded into artificial casing and linked on a stainless steel frame (Fig. 19). This frame was designed to produce wieners of uniform length; the frame is also used to hold wieners in the smoke tunnel for curing (Fig. 20).

In developing the formula for wieners, various cooking times and tempera­ tures were tested to establish a procedure for removing the artificial casing. Cooking in water at 160 F for 15 min caused a toughening of the surface protein; wieners cooked in a microwave oven for 5 sec had desirable texture and tenderness and

FIG. 19. First step in forming wieners on triangular steel frame.

24 FIG. 20. Fish wieners on frame in smoke tunnel.

lacked surface toughness; microwave ovens have not yet been used commercially for heating wieners before peeling off the casing; however, it was found that wieners cooked in water at 160 F for 5 min had reasonably satisfactory texture.

FREEZE - DRYING Freeze-drying of freshwater fishery products has been limited to a few tests carried out with the assistance of the Defense Research Board in Toronto. Pickerel steaks i inch thick, pickerel fillets, and minced pickerel pressed into i-inch flat rounds to form patties were freeze-dried satisfactorily in a sub­ limator. The products rehydrated well and, when cooked, had good flavor. These tests, despite the limited nature of the trials, indicated that there is a potential for some freeze-dried products.

PACKAGING AND STORING One of the misconceptions regarding smoked fish is that it can be kept in­ definitely without benefitof refrigeration. Fish that are mild-cured are not protected sufficiently by salt-curing to permit holding at temperatures above that of approved refrigerated storage. Products for storage of more than a few days should be frozen and stored at sub-zero temperatures (-15 F, or lower). When refrigerated storage does not include controlled humidity within the storage area, glazing of the product is recommended.

GLAZING The term "glaze" refers to a coating which is applied to frozen products as protection from drying or dehydration. Glaze also protects the product from oxidation of fats, by excluding oxygen, which brings about discoloration and rancidity.

25 Numerous types of glaze have been introduced but ice glazes are generally favored and are inexpensive. An ice glaze is applied by immersing the frozen fish in pure water (Piskarev and Gakichko, 1957) or in an approved chemical glaze like disodium hydrogen phosphate in a ratio of exactly 3 Ib to 100 lb of water (Fisheries Research Board of Canada, 1936). In Imperial measure, 100 Ib of water equals 10 gal. Use of this glazing solution is permitted in Canada, and is recommended as being superior to pure water because it produces a glaze which is less brittle and does not chip offas readily. The chemical formula Na2HP04. 12H20 should be used when purchasing disodium hydrogen phosphate to avoid confusion with other phosphates. The glazing solution is prepared by mixing the disodium hydrogen phosphate with some water from the glazing tank to form a thin paste; the paste is added to the remaining water in the glazing tank and dissolved by thorough mixing. Temperature of the glazing solution should be maintained at about 33 F. At temperatures below 33 F, ice crystals form and adhere to the glaze as fish are removed from the glazing tank. Fish which are to be glazed should be kept in frozen storage at a temperature of -15 F. When the fish are dipped in the glazing solution (33 F), the temperature of the fish rises slightly since they absorb heat from the dipping solution; at the same time, the temperature of the glazing liquid which comes in contact with the fish is lowered causing the liquid to freeze. Frozen fish are submerged in the glazing solution for 1 min per dip, allowing 3 min out of solution between dips. Three I-min dips provide a satisfactory pro­ tective glaze which does not crack under ordinary circumstances. When fish are removed from the final dip, they are left in the dipping rack only until the frozen solution stops dripping. The glaze should appear wet and slightly opaque (giving the fish a whitish appearance) when returned to storage (- 15 F). If fish stick to­ gether or stick to the dipping rack, the glaze must be broken to separate them, and its value is lost. Alginate gel coatings (Anon., 1957) provide protection similar to that of a good glaze. Fish are coated with an alginate jelly made from seaweed extract, and frozen. The coating is reported to offer the product complete protection from air, thus retarding rancidity and moisture loss.

REFRIGERATED STORAGE CHAMBERS It is possible to reduce moisture loss and eventual desiccation of fish products by controlling both temperature and humidity within the storage chamber. When air is saturated with moisture (relative humidity 100%) at any given temperature, desiccation of frozen fish is minimized. This type of storage is called "jacketed cold storage" and involves circulating refrigerated air through passages in a sealed jacket on the perimeter walls, floor, and ceiling of the storage chamber (Young, 1952; Lentz and Cook, 1955; Eddie, 1957; Lantz, 1964c) (Fig. 21). Owing to a

26 FIG. 21. Elevation showing air-jacket system of a cold storage plant described by Lantz (l964c). small temperature difference (2 F degrees) between the air in the jacket and the temperature inside the storage area, it is possible to maintain a very high relative humidity. Because the air in the jacket does not come in contact with stored pro­ ducts, it cannot draw moisture away from them.

PACKAGE MATERIALS Materials used for packaging fishery products include a wide variety of films, wraps, bags, cartons, and cans. Some of the transparent films resist tearing, are sufficiently pliable to permit a tight wrap, and are greaseproof and durable at low temperatures. Packaging materials should have a low rate of moisture- and vapor-permeability and should impart no odors or flavors (Anon., 1963b). Among the products used are cellophane, polyethylene, aluminum foil, and vinylidene chloride. Very thin-gauge aluminum foil, when laminated to paper which has been coated with polyethylene, makes an excellent overwrap for fish (Peters, 1960). Plastic films are strong, flexible, transparent, and chemically inert ; when properly applied and heat-sealed, they provide an effective ba rrier against dehy­ dration and oxidation. Extruded film pouches, which fit the product snugly, re­ portedly extend the storage life of the product by more than two times that of conventionally packaged fish (Bloomberg, 1960). Boil-in-the-bag frozen foods are becoming familiar items to the shopper; this form of packaging has proven suitable for many types of fish products. A popular material for this purpose is a lamination of medium-density polyethylene and polyester film (Doar, 1960). Cartons in general use for frozen fish are waxed cardboard, rectangular in shape, and self-locking (Pottinger and Miyauchi, 1956). Cardboard cartons with cellophane windows are frequently used for packaging frozen cooked fish portions.

27 In the packaging of fresh and smoked fish, there are still many technical problems to be solved. As is the case with frozen fish, packaging materials least permeable to oxygen and carbon dioxide yield a longer shelf life (Anon., 1963a).

CANS Cans used for fishproducts require a protective coating on the inside to prevent corrosion and tin sulphide discoloration which occurs when sulphur-bearing products, like fish, are processed in plain cans (Stevens and Ellis, 1960). Enamels for this purpose are made from synthetics including hydrocarbon resins, phenolic types such as phenol formaldehyde and related cresol-aldehyde resins, vinyls, maleic alkyds, urea-formaldehyde, styrenes, epons, and others. The inside coatings are expected to resist chemical action of food acids and essential oils. Lining materials must be nontoxic and taste-free. A coating must not soften, disintegrate, or lose adhesion when SUbjected to food-processing temperatures. Flexibility and film continuity are claimed to be most important qualities in protective enamels for food containers. Cans used for fishery products are ordered with the specifica­ tion "latest type of enamel for fish."

Can manufacturers designate round can size by width X depth, e.g. 307 X 200. The first digit in each number represents inches and the last one or two digits represent sixteenths of an inch, so that 307 is 3176 inches and the second number 2 inches. Oblong can sizes are designated by length X width X depth, e.g. the dimensions 405 X 30 1 X 014 indicate that the can is 4ft- inches long, 31\ inches wide, and tt inch deep.

STORAGE AND KEEPING QUALITIES OF PRODUCTS The quality of special products is dependent upon a number of factors : fresh­ ness of the fish ; purity of each additive (spices from some sources have a high bacterial count); sanitation of the processing area; suitable temperature in the processing area (50-60 F); correct humidity (40-50%); standardized techniques; and adequate supervision to assure cleanliness and health of the workers. A sepa­ rate, self-contained, well-ventilated area for preparation and processing of products is recommended. The room should be of material which permits maintenance of cleanliness and rapid washdown.

Storage requirements are dependent upon the products to be held and length of the storage periods. Products should be frozen at -30 F, or lower, and should be stored at temperatures not exceeding -15 F.

Bogoslowski (1965) has considered the keeping qualities of fish sausages and wieners in detail.

Fish sausages are prone to very rapid spoilage. If they are to be stored for more than a day or two, it is essential that they be frozen and stored at -15 F or lower. Storage life of unfrozen sausages held at household refrigerator tempera­ ture (35-40 F) is about 1 day, or possibly 3 days maximum, depending upon bac­ terial contamination of the sausage mixture and any surface contamination which may have occurred. Thawed sausages should be cooked immediately.

28 Wieners have a longer shelf life in the unfrozen state than sausages. This is due to the hot-smoke treatment and to the treatment at 160 F before removal of the synthetic casing. Maximum shelf life at household refrigerator temperature is approximately 2 weeks. Frozen storage at -15 F, or lower, is recommended. Like sausages, wieners should be cooked as soon as possible after thawing.

Canned products which have been processed according to techniques described in this Bulletin require no specific treatment other than that usually given canned foods.

FORMULAS FOR PRODUCTS

Numbered fo rmulas for preparing special products from freshwater fish fo llow. They are divided into five categories : Canned Fish (Formulas 1-9) ; Fish­ balls (Servies) (Formulas 10-14) ; Sausages (Formula 15) ; Smoked Fish (Formula 16) ; and Wieners (Formulas 17-20).

Format for the fo rmulas was selected for its practicability in actual situations. Each fo rmula may be used as a process chart and procedure may be fo llowed simply by reading across each line, the same as reading a page of text ; ingredients and procedures are given in sequence.

DRESSED ALEWIFE :s SMOKED, AIR-DRIED, AND CANNED Form.ula 1

Procedure Amount Material or ingredients Sal Time Temp

Prepare salt brineb 80c In salt brine immerse dressed alewife It min 60 F Remove alewife ; drain on screens for 1 min Place alewife in smoke tunnel and smoke 45 min 160 F Dry alewife, without smoke, in tunnel 75 min 160 F Remove alewife from smoke tunnel ; trim offtails and rough edges Pack alewife in 4-oz oblong cansd To each can add ! oz vegetable oil Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure (10 psi)e 15 min 40 F Remove cans from retort ; dry, label, and store

BDressed alewife = approximately 40/lb. bTo prepare salt brine, refer to brining instructions on page 7. eTo prepare 80 sal brine, refer to Table II, page 8. dean size 405 X 301 X 014. When ordering cans (drawn containers) specify the latest type of enamel for fish. epsi = pounds per square inch.

29 3 DRESSED CAPELIN : SMOKED, AIR-DRIED, AND CANNED Formula 2

Procedure Amount Material or ingredients Sal Time Temp Prepare salt brineb 80C In salt brine immerse dressed capelin 1 min 60 F Remove capelin ; drain on screens for 1 min Place capelin in smoke tunnel and smoke 30 min 160 F Dry capelin, without smoke, in tunnel 80 min 160 F Remove capelin from smoke tunnel ; trim offtails and rough edges Pack capelin in 4-oz oblong cansd To each can add � oz vegetable oil Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure (10 psi)e for 15 min 40 F Remove cans from retort ; dry, label, and store

3Dressed capelin, males = approximately 24-30/lb. bTo prepare salt brine, refer to brining instructions on page 7. cTo prepare 80 sal brine, refer to Table II, page 8. dCan size 405 X 301 X 014. When ordering cans (drawn containers) specify the latest type of enamel for fish. epsi = pounds per square inch.

a DRESSED SMELT : SMOKED, AIR-DRIED, AND CANNED Formula 3

Procedure Amount Material or ingredients Sal Time Temp Prepare salt brineb 80c In salt brine immerse dressed smelt � min 60 F Remove smelt ; drain on screens for 1 min Place smelt in smoke tunnel and smoke 15 min 160 F Dry smelt, without smoke, in tunnel 80 min 160 F Remove smelt from smoke tunnel ; trim offtails and rough edges Pack smelt in 4-oz oblong cansd To each can add ! oz vegetable oil Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure (10 psi)e for 15 min 40 F Remove cans from retort ; dry, label, and store

aDressed smelt = 24-30/lb. bTo prepare salt brine, refer to brining instructions on page 7. cTo prepare 80 sal brine, refer to Table II, page 8. dCan size 405 X 301 X 014. When ordering cans (drawn containers) specify the latest type of enamel for fish. epsi = pounds per square inch.

30 DRESSED ALEWIFE :& SMOKED, COOKED IN OIL, AND CANNED Fonnula 4

Procedure Amount Material or ingredients Sal Time Temp

Prepare salt brineb 80e In salt brine immerse dressed alewife It min 60 F Remove alewife ; drain on screens for 1 min Place alewife in smoke tunnel and smoke for 15 min 160 F Remove alewife from smoke tunnel; cook in hot corn oil for 15 min 220 F Drain alewife ; trim offtail and rough edges ; pack alewife in 4-oz oblong cansd Place cans in can-closing machine; seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure 110 psi)" for 1 5 min 40 F Dry, label, and store cans

aDressed alewife = approximately 40/lb. bTo prepare salt brine, refer to brining instructions on page 7. eTo prepare 80 sal brine, refer to Table II, page 8. dCan size 405 X 301 X 014. When ordering cans (drawn containers) specify the latest type of enamel for fish. "psi = pounds per square inch.

ALEWIFE FILLETS :& SMOKED, AIR-DRIED, AND CANNED Forllluia 5

Procedure Amount Material or ingredients Sal Time Temp

Prepare salt brineb 80e In salt brine immerse alewife fillets 1 5 sec 60 F Remove alewife and drain skin side down on screens for 1 min Place alewife in smoke tunnel and smoke for 1 5 min 160 F Dry alewife, without smoke, in tunnel for 60 min 160 F Remove alewife from smoke tunnel ; trim offrough edges ; pack alewife in 4-oz oblong cansd To each can add ! oz vegetable oil Place cans in can-closing machine; seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure (10 psi)" for 15 min 40 F Dry, label , and store cans

& Alewife fillets = approximately 24/lb. DTo prepare salt brine, refer to brining instructions on page 7. eTo prepare 80 sal brine, refer to Table II, page 8. dCan size 405 X 301 X 014. When ordering cans (drawn containers) specify the latest type of enamel for fish. epsi = pounds per square inch.

31 CHUB FILLETS :" SMOKED, AIR-DRIED, AND CANNED Forlllula 6

Procedure Amount Material or ingredients Sal Time Temp

'Prepare salt brineb SOc In salt brine dip chub fillets 5 sec 60 F Remove chub and drain skin side down on screens for 1 min Place chub in smoke tunnel and smoke for 15 min 160 F Dry, chub, without smoke, in tunnel for 90 min 160 F Remove chub from smoke tunnel ; trim offrough edges ; pack chub in 4-oz oblong cansd To each can add � oz vegetable oil (optional) Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure (10 psi)" for 15 min 40 F Dry, label, and store cans

"Chub fillets = 16-18/lb. bTo prepare salt brine, refer to brining instructions on page 7. "To prepare SO sal brine, refer to Table II, page 8. dCan size 405 X 301 X 014. When ordering cans (drawn containers) specify the latest type of enamel for fish.

epsi = pounds per square inch.

FRESHWATER EEL FILLETS : SMOKED , AIR-DRIED, AND CANNED Forllluia 7

Procedure Amount Material or ingredients Sal Time Temp

Prepare salt brinea In salt hrine immerse skinless eel fillets 5 sec 60 F Remove eel and drain on screens for 1 min Place eel in smoke tunnel and smoke for 15 min 160 F Dry eel, without smoke, in tunnel for 60 min 160 F Remove eel from smoke tunnel ; pack eel in 4-oz oblong canse To each can add 10Z vegetable oil (optional) Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for 50 min 240 F Leave cans in retort and cool in water under pressure (10 psi)d for 15 min 40 F Dry, label, and store cans

aTo prepare salt brine, refer to brining instructions on page 7. bTo prepare SO sal brine, refer to Table II, page S. eCan size 405 X 301 X 014. When ordering cans (drawn containers; specify the latest type of enamel for fish.

dpsi = pounds per square inch .

32 FRESHWATER CODa LlveRS :o SMOKED AND CANNED

Procedure Amount Mate,ieJ

Prepare 9 gal To salt brine add and mix 10 oz To brine and saltpetree add Soak livers Remove livers ; drain on screen for Place livers in smoke tunnel and smoke for F Remove livers from smoke tunnel Pack livers in To each can add I! tsp Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for F Leave cans in retort and coo! in water under pressure (10 psi)g Dry, label, and store cans

aFreshwater cod is also known as burbot, ling, bLivers weigh approximately 8 oz per fish. eTo prepare salt brine, refer to brining instructions dTo prepare 75 sal brine, refer to Table II, 8. ·One gallon of brine-and-saltpeter solution .5 Ib tCan size 405 X 301 X 014. When ordering cans (drawn of enamel for fish. gpsi = pounds per square inch.

FRESHWATER FISH :" CANNED STEAK-STYLEb

Procedure

Cut crosswise in l!-inch slices Pack in Add to each can salt Place cans in can-closing machine ; seal under 20-inch vacuum Place cans in retort ; sterilize for Leave cans in retort and coo! in water under pressure (10 psi)e F Remove cans from retort ; dry, label , and store

"Chub, inconnu, sheepshead, sucker, lake tront, b Under this process there may be free liquid process as follows : in smoke tunnel (without smoke) upon degree of dryness desired ; refrigerate fish for for canned freshwater fish steak-style. cCan size 307 X 200. When ordering cans, specify the latest d A small headspace (k-t inch) is essential when expansion of the product during processing. A space of fish solids during transport. epsi = pounds per square inch.

33 FISHBALLS (SERVIES) FROM FRESHWATER FISH& Forll1ula 10

Procedure Amount Material or ingredients Time Temp

Start food cutter ; add Sib fillets 32 F Chop for ! min Add and mix 80z vegetable shortening ! min 33-35 F Add and mix 6! oz frozen chopped onion ! min 30 F Add and mix sifted dry ingredients : I! oz salt 1 tsp thyme ! tsp ginger ! tsp savory 40z wheat flour 2! oz milk powder min Shape mixture into balls using ! oz mixture for each ; roll balls in flour and deep fry in vegetabll;! oil 4 min 380 F Drain on rack for 1 min

&Sucker, carp, sheepshead, or whitefish.

WHITE SAUCE FOR CANNED FISHBALLS (SERVIES)& Forll1ula 11

Procedure Amount Material or ingredients Time Temp

Place I! Ib clean fishbone s In 4 qt water Add : I lb onions, cut up 40z celery, cut up 20z lemon juice 10 peppercorns Heat to boiling and simmerb fOl 30 min Skim offscum ; drain and retain stock Heat and blend : 10 0z corn oil 10 0z flour 3 min 275 F Mix to a smooth paste Gradually add stock to the paste ; heat to boiling 212 F Add : 1 oz salt � oz pepper Stir until smooth ; simmerb for 30 min

SInstructions for preparing fishballs (servies) are given in Formula \0 bCook over direct heat just below boiling point (180-210 FI.

34 b CANNED FISHBALLS (SERVIES)& IN WHITE SAUC'E Formula 12

Procedure Amount Material or ingredients Time Temp

Place 50z (6-8) fishballs In 8-oz round cans" While still hot, pour over fishballs 30z white sauce Place cans in can-closing machine and seal under 20-inch vacuum Place cans in retort and sterilize for 90 min 240 F Leave cans in retort and cool in water under pressure (10 psi)d for 30 min 40 F Dry, label, and store cans

BInstructions for preparing fishballs (servies) are given in Formula 10. blnstructions for preparing white sauce are given in Formula II. "Can size 307 X 200. When ordering, specify the latest type of enamel for fish.

dpsi = pounds per square inch.

R BAKED BEANS (FOR FISHBALLS WITH BEANS) Formula 13

Procedure Amount Material or ingredients Time Temp

In 1 qt water 40 F Soak 16 0z beans (navy or kidney) 14 hr Heat to boiling and simmerb for 30 min 200 F Skim off scum, drain and retain liquor To liquor add : 30z chopped onion 10z sugar 10z molasses 2! oz tomato paste 1 tsp cider vinegar 1 tsp Worcestershire sauce ! oz salt i tsp dry mustard 1 tsp white pepper ! tsp cinnamon ! tsp allspice 1 bay leaf Heat to boiling 212 F Add cooked beans, place in oven and bake, stirring occasionally, for 4 hr 250 F

Rlnstructions for preparing fishballs are given in Formula 10. bCook over direct heat just below boiling point (180-210 F.)

35 or

5 (6-8)

3 cooked beans

Place

Place 90 240

Leave under pressure (10

Dry, and store cans

SInstructions for preparing fishbal ls are given bInstructions preparing beans 307 X 200. When specify type of for fish. pcr inch.

FRESHWATER

ingredien is Tirne

Start .5

Blend 2

Ib hydrogenated shortening

Blend fo r

In

Extrude into casingC

Link by wa.xed cartons

cartons of sausages 40 F

For long storage refrigerate -30 F

"Whitefish, carp, smelt, sheepshead , b Addition of � Ib of ice to 5 lb maintains temperature near 35 F during mixing. CNatural casing (sheep intestines) or (casing (collagen). SI\10KING OF DRESSED FRESH\A/ATER Fl;<;i"ft 16

Procedure Material or ingredients

Place 60 F screens drain Place fish in smoke tunnel and smoke for 70 F Then increase temperature by 10° ?,very 15 min to F Increase to 180 F and smoke fo r F Remove fish smoke tunnel ; chilI fish in cold room F fish -40 F or package fish and store at F

"Whitefish, sucker, carp, lake trout, chub, goldeye, large alewife, large

refer to brining instructions on page 7. refer to Table II, page 8. reqUlred depend upon species and size of fish. wi II depend upon size of fish and efficiency of freezer. preparing and applying glaze are given on page 25.

FRESHWATER FISH'" WIENERS Forn:mla 17

Procedure Amount Material Temp

finest cutting blade, homogenize fo od mill 1 I b fish flesh containing bones min F �-inch cutting blade, coarse-cut fo od mill 41b 32 F Place in fo od culter , start cutter and add : 4 oz 2 tsp 1 tsp Blend fo r Lei stand fo r 40 F Return mixture to food cutter ; and add : 12 0z shorten1ng 302 oz 80z crushed ice Blend for 2 Place mixture in casing ; place on triangular steel frames fo rm wieners ; place frames of wieners in smoke tunnel and smoke for 15 min 120 F Then increase temperature by J00 every 15 min to 160 F I ncrease temperature to 180 F and smoke for 60 min 180 F Remove wieners from smoke tunnel ; immediately immerse wieners in hot water 5 min 160 F Chill wieners by cold-water immersion or cold-water spray 10 min 40 F Peel and package wieners ; plate freeze at --40 F Store at -15 F

aBullhead, whitefish, sheepshead, carp, bullhead with carp and sheepshcad, chub with whitefish, chub with suckers, and suckers with carp. bpepper oil 17% ; nutmeg oil 6%; coriander oil 9%; cloves l!%; onion powder 4 �%; paprika 21 %; salt 41 %. "Commercially prepared binder preferred.

37 " SWEET-AND-SOUR SAUCE (FOR WIENERS CANNED IN SWEET-AND-SOUR SAUCE) Formula 18

Procedure Amount Material or ingredients Time Temp

Blend : 16 0z tomato sauce 40z corn syrup 20z cider vinegar 2 tbsp Worcestershire sauce 2 tsp prepared mustard 2 drops Tabasco sauce 1 tsp celery seed 20z minced onions

Heat to boiling blended sauce 212 F

Simmerb sauce for 30 min

"To prepare fish wieners, see Formula 17. bCook over direct heat just below boiling point (180-210 F) .

FRESHWATER FISH WIENERS" CANNED IN BRINE Formula 19

Procedure Amount Materia! or ingredients Sal Time Temp

Cut in pieces 1 i-inches long 12 wieners

Stack pieces upright in 8-oz round cansb

Cover wieners with hot salt brinec Sd

Place cans in can-closing machine and seal under 20-inch vacuum

Place cans in retort and sterilize for 90 min 240 F

Leave cans in retort and cool in water under pressure (10 psi)8 30 min 40 F

Dry, label, and store cans

"To prepare fish wieners, see Formula 17. bCan size 307 X 200. When ordering cans, specify the latest type of enamel for fish. cTo prepare salt brine, refer to brining instructions on page 7. dTo prepare 5 sal brine, refer to Table II, page 8.

epsi = pounds per square inch.

38 " b FRESHWATER FISH WIENERS CANNED IN SWEET-AND-SQUR SAUCE Formula 20

Procedure Amount Material or ingredients Time Temp

Cut in pieces 1 i-inches long 12 wieners

Stack pieces upright in 8-oz round cans"

Cover wieners with sweet-and-sour sauce

Place cans in can-closing machine and seal under 20-inch vacuum

Place cans in retort and sterilize for 90 min 240 F

Leave cans in retort and cool in water under pressure (10 psi)d 30 min 40 F

aTo prepare fish wieners, see Formula 17. bTo prepare sweet-and-sour sauce, see Formula 18. "Can size 307 X 200. When ordering cans, specify the latest type of enamel for fish.

dpsi = pounds per square inch.

ACKNOWLEDGMENTS The author gratefully acknowledges the assistance and cooperation of Mr David Iredale who produced innumerable processings of products, helped with their development and prepared samples for tasting and display; he is indebted to Mrs A.W. Lantz and the School of Nursing, Victoria Hospital, London, for helping to produce the formulas and for conducting taste tests of experimental products; Mr Sheldon Zettler prepared numerous drawings, sketches, and photo­ graphs to illustrate the text. A special word of appreciation is due Mrs Joyce De Serranno for her conscientious effort in checking references, typing the manu­ script, and assisting in many ways. Cooperation of Union Carbide Company, Visking Division, Toronto, Devro Co., Somerville, N.J., and Griffith Laboratories, Toronto, is acknowledged. The Department of Fisheries Inspection Service supervised capture, processing, and shipment of whitefish from Saskatchewan; the Fish Inspection Laboratories in Vancouver and Halifax provided results of taste tests made on canned whitefish and the Defense Research Board provided facilities for freeze-drying products.

39 BIBLIOGRAPHY

AMANO, KElSHI. 1962. Fish sausage processing in Japan. Fishing News Intern. , 1(5) : 29-30, 32-34.

AMERICAN MEAT INSTITUTE FOUNDATION. 1960. The science of meat and meat products. Reinhold Publishing Corp., New York. 438 pp.

ANON. 1950. Friday franks. Fishing Gazette, 67(2) : 28. 1955. Versatile unit protects fishduring scaling. Food Eng., 27(9) : 1 39. 1957. Fillets coated with alginate jelly exported by Norwegians. West. Fish., 55(1) : 28. 1958. Seafood produce made from tuna is like hot-dog. Food Field Reporter, 26(1) : 4. 1958. Tuna hot dog is established in new markets in the east. Seafood Merchand., 18(1 0): 10. 1959. Guide to "Canada Inspected" standards. Part 2. Sanitation and processing operations. Canadian Fisherman, 46(10) : 21-28. 1960. Guide to "Canada Inspected" standards. Part 5. What constitutes a suitable product ? Ibid., 47(1) : 19-25. 1960. Canning machinery. Food Mfr., 38(8) : 334-37, 350. 1961. Fish challenges meat on its own grounds - in tuna-links, a meatless hot dog. Fishing Gazette, 78(3) : 14-1 5, 31. 1961. Nichiro fish sausage center. Pacific Fisherman Intern., 59(8) : 11-12. 1962. Advances in processing methods. Food Eng., 34(2) : 37-52. 1963a. Packaging problems with fresh fish. New Scientist (London), 19(7) : 11. 1963b. How to select packaging films on basis of gas permeability. Fish Boat, 8( 1 0) : 33, 48.

BABBIIT, HAROLD E. 1952. Engineering in public health. McGraw-Hill Book Co., Inc., New York. 582 pp.

BLOOMBERG, RAY. 1960. Fish-in-bags hook plus-sales. Food Eng., 32(6) : 99.

BOOOSLOWSKI, A. S. 1965. The keeping qualities of fish sausages and wieners. Fish. Res. Bd. Canada, London BioI. Sta. Tech. Unit Circ. No. 7, pp. 1-8.

BORGSTROM, GEORG. (ed) . 1961. Fish as food. Volume 1. Production, biochemistry, micro­ biology. Academic Press, New York. 725 pp. 1962. Fish as food. Volume 2. Nutrition, sanitation, utilization. Academic Press, New York. 777 pp.

BROWN, W. G., AND C. P. LENTZ. 1956. Moisture absorption by some packaging materials at subfreezing temperatures. Canadian J. Tech., 34 : 366-372.

CASTELL, C. H. 1954. Spoilage problems in fresh fishproduction. Bull. Fish. Res. Bd. Canada, No. 100, pp. 10-12. 1958. A simple method of checking on the sources of contamination in fish plants. Fish. Res. Bd. Canada, Atlantic Prog. Rept., No. 70, pp. 23-27.

CASTELL, C. H., J. S. M. HARRISON, AND O. C. Young. 1960. Handling, chilling and freezing fish. Canadian Fisherman, 47(2) : 19-25.

CHIVILENKO, V. P., AND I. I. VEDERNIKOV. 1 960. Machine for gutting small fish. raelIs Program for Scientific Translations, PST Cat. (Office Technical Services, U. S. Dept. Com­ merce, Washington) No. 68 (OTS 60-21-96). 4 pp. [Trans. from Russian.]

40 CLAGGETT, F. G. 1962. Packaging air shipments of fresh fish. Fish. Res. Bd. Canada, Pacific Prog. Rept., No. 114, pp. 3-5. COPSON, DAVID A. 1962. Microwave heating in freeze-drying, electronic ovens, and other applications. AVI Publishing Co. Inc., Westport, Conn. 433 pp.

CUTTING, C. L. 1948. Torry Research Station controlled fish smoking kiln. Dept. Sci. Ind. Res., Food Invest. Mem. 596. 18 pp. Repr. from The British Fish Manual and Directory.

DEMPSEY, H. V. 1962. Fish processing plant water supplies. Canadian Fisherman, 49(6) : 66-67. 1964. Inspection and quality control. Ann. Rev. 1964 Fish. Counc. Canada, nineteenth Ann. Meet., April 20-22, Charlottetown, p. 57.

DEPARTMENT OF FISHERIES. 1958. Methods for canning suckers. Trade News, 10(10) : 16.

DEPARTMENT OF NATIONAL HEALTH AND WELFARE. 1964. 1954 office consolidation of the Food and Drug Act and of the Food and Drug Regulations with amendments to June 18, 1964. Sect. B.21.020 (a) and (b) , p. 71A, Nov. 7, 1963. Queen's Printer, Ottawa.

DEPARTMENT OF SCIENTIFIC AND INDUSTRIAL RESEARCH. 1959. Torry Research Station Annual Report 1958. Handling and preservation of fish. Torry Res. Sta., Aberdeen, p. 19. 1960. Torry Research Station Annual Report 1959. Torry Res. Sta., Aberdeen. 31 pp. 1961. Torry Research Station Annual Report 1960. Torry Res. Sta., Aberdeen. 44 pp. 1962. Torry Research Station Annual Report 1961. Torry Res. Sta., Aberdeen. 44 pp. 1963. Torry Research Station Annual Report 1962. Torry Res. Sta., Aberdeen 44 pp. 1964. Smoked fish - recommended practice for retailers. Torry Res. Sta., Aberdeen, Torry Advisory Note No. 14. 6 pp.

DOAR, LE Roy H., JR. 1960. The technology of boil-in pouches. Frosted Food Field, 30(2) : 28-29, 40. DOMINION BUREAU OF STATISTICS. 1964a. Fisheries Statistics Ontario 1962. Queen's Printer, Ottawa, p. 8. 1964b. Fisheries Statistics Manitoba 1962. Queen's Printer, Ottawa, p. 6. 1964c. Fisheries Statistics Saskatchewan 1962. Queen's Printer, Ottawa, p. 5. 1964d. Fisheries Statistics Alberta 1962. Queen's Printer, Ottawa, p. 5.

DUGAL, L. C. 1962. Proximate composition of some freshwater fish. Fish. Res. Bd. Canada, London BioI. Sta. and Tech. Unit Circ. No. 5, pp. 1-6.

DYER, W. J. 1957. Storage and transportation of frozen fish. Canadian Fisherman, i4(6) : 37, 39, 41, 43. EDDIE, G. C. 1957. A review of the development of jacketed cold stores for frozen foods. Modem Refr., 60(711) : 225-227.

ELLIS, WAYNE P. 1964. Interior finishes for cold storage facilities. ASHRAE (Am. Soc. Heat., Refr. and Air-cond. Eng.) J., 6(12) : 48-50.

FISHERIES RESEARCH BOARD OF CANADA. 1936. Instructions for making an improved type of ice glaze for frozen fish. Pacific Fish. Exptl. Sta., Prince Rupert, B.C. Ind. Mem. No. 2. 3 pp. (mimeo). 1949. Fish scaler and washer. Fish. Res. Bd. Canada, Pac. Prog. Rep. No. 78, p. 16. 1958. Selected publications concerning smoked fish. Fish. Res. Bd. Canada, Tech. Sta., Vancouver Circ. No. 22.

FOSTER, W. W., AND T. H. SIMPSON. 1961. Studies of the smoking process for foods. I. The importance of vapors. J. Sci. Food Agr., 12 : 363-374. HARRIS , ROBERT S., AND HARRY VON LOESECKE, (ed). 1960. Nutritional evaluation of food processing. John Wiley & Sons, Inc., New York. 612 pp.

41 HARRISON, J. S. M., AND S. W. ROACH. 1952. The application of vacuum in pretreatment of fish for canning. Fish. Res. Bd. Canada, Pac. Prog. Rep. No. 91, pp. 10-12. HEEN, EIRIK, AND RUDOLF KREUZER (ed) . 1962. Fish in nutrition. Fishing News (Books) Ltd., London. 445 pp. HOPPER, P. F. 1963. Protein filmmakes superior sausage casing. Food Eng., 35(9) : 102-103.

HUSSAINI, SAEED A, AND G. E. COOPER. 1957. Fractionation of wood smoke and the comparison of chemical composition of sawdust and friction smokes. Food Tech., 11(10) : 499-502.

IVES, MARGARET, AND GAIL M. DACK. 1957. Safety of inside enamel coatings used in food cans. Food Res., 22(1) : 102-109.

JARVIS, NORMAN D. 1943. Principles and methods in the canning of fishery products. U. S. Fish and WildI. Servo Res. Rep. No. 7, 366 pp. 1950. Curing of fishery products. Ibid., No. 18, 271 pp.

JOHNSON, W. BLOIS. 1960. Hygienic considerations in food plant design. Chemistry and Industry, No. 39, pp. 1203-1206.

KAREL, M., B. E. PROCTOR, AND G. WISEMAN. 1959. Factors affecting water-vapor transfer through food packaging films. Food Tech., 13(1) : 69-74.

KARRICK, NEVA, WILLIAM CLEGG, AND MAURICE E. STANSBY. 1956. Composition of fresh­ water fish - No. 1. Comm. Fish. Rev., 18(2) : 13-1 6.

KRAMER, AM IHUD , AND BERNARD A TWIGG. 1962. Fundamentals of quality control for the food industry. AVI Publishing Co. Inc., Westport, Conn. 512 pp.

LANTZ, A. W. 1945. Specialty products from smoked and cooked fish. Fish. Res. Bd. Canada, Pac. Fish. ExptI. Sta., Vancouver Ind. Mem. No. 7, 3 pp. (mimeo.) 1947. Herring products. Fish. Res. Bd. Canada, Pac. Prog. Rep. No. 72, pp. 33-35. 1948a. Experiments on the canning of freshwater fish. Ibid., No. 74, pp. 19-21. 1948b. Experiments on the smoking of freshwater fish. Ibid., No. 75, pp. 35-39. 1949. An air-conditioned tunnel for processing fish. III. A commercial conveyor-type vertical kiln. Ibid., No. 81, pp. 87-90. 1961a. The Lake Erie gear development project - 1959. Fish. Res. Bd. Canada, London BioI. Sta. and Tech. Unit Prog. Rep. No. 2, pp. 5-14. 1961b. Canning freshwater fish. III. Ibid., _pp. 37-47. 1962. Specialty fish products. Fish. Res. Bd. Canada, London BioI. Sta. and Tech. Unit Circ. No. 4, pp. 10-20. 1963. Fresh whitefish sausage. Ibid., No. 6, pp. 17-23. 1964a. A practical method for cleaning and dressing fish. Trade News, 16(11) : 6-8. 1964b. A practical method for brining and smoking fish. Ibid., 16(12) : 14-17. 1964c. Fish cold storage plant ; Mutwal, Ceylon. ASHRAE (Am. Soc. Heat., Refr. and Air-cond. Eng.) J., 6(8) : 38-40. 1965. A practical method for canning fish. Trade News, 17(8) : 3-8. LANTZ, A. W., AND L. C. DUGAL. 1959. Experiments on canning freshwater fish. II. Smelts from west end of Lake Erie. Fish. Res. Bd. Canada, BioI. Sta. and Tech. Unit, London Prog. Rep. No. 1, pp. 28-30. LANTZ, A. W., AND O. C. YOUNG. 1949. An air-conditioned tunnel for processing fish. III. Fish. Res. Bd. Canada, Pacific Prog. Rep. No. 78, pp. 17-20. LENTZ, C. P. 1955. Humidification of cold storages ; the jacket system. Canadian J. Tech., 33 : 265-278. LENTZ, C. P., AND W. H. COOK. 1955. Comparison of two types of high humidity cold storage systems. Proc. Ninth Intern . Congress Inst. Refr., Pa!is, 1955, 5: 039-044.

42 LEUNG, W.-T. Wu. 1962. Problems in compiling food composition data. J. Am. Diet. Assoc., 40 : 19-22.

LINTON, E. P., AND A. L. WOOD . 1943. A tunnel smoke-house for the smoke curing of fish. Fish. Res. Bd. Canada, Atl. Prog. Rept. No. 34, pp. 10-14.

LITTLE, ARTHUR D., INC. 1958. Flavor research and food acceptance. Reinhold Publishing Corp., New York. 391 pp.

LORANT, MICHAEL. 1963. Fish sausages. Food Mfr., 38 : 413-414.

LoTZ, WILLIAM A. 1964. Vapor barrier design for cold storage applications. ASHRAE (Am. Soc. Heat., Refr. and Air-cond. Eng.) J., 6(12) : 46-48.

LOWE, BELLE. 1961. Experimental cookery. John Wiley & Sons, Inc., New York, 573 pp.

MACCALLUM, W. A. 1963. Factors influencingthe effectiveness of fresh fishwashing operations. J. Fish. Res. Bd. Canada, 20 : 1231-1244.

MATZ, SAMUEL A. 1962. Food Texture. AVI Publishing Co. Inc., Westport, Conn., 286 pp.

MCGARVEY, ALAN R. 1964. Wrap your cold storage room in a vapor barrier. ASHRAE (Am. Soc. Heat., Refr. and Air-cond. Eng.) J., 6(12) : 42-46.

MERORY, JOSEPH. 1960. Food flavorings-composition, manufacture and use. AVI Publishing Co. Inc., Westport, Conn., 381 pp.

MEYER, LILLIAN HOAGLAND. 1960. Food chemistry. Reinhold Publishing Corp., New York, 385 pp.

MIYAUCHI, DAVID T. 1963. Drip formation in fish. 1. A review of factors affecting drip. U. S. Fish and Wildl. Servo Fishery Ind. Res., 2(2) : 13-20.

MONTGOMERY, W. A., AND A. R. PRATER. 1963. Fish preservation inquiries. Fisheries products. Fish sausages (1), (3) and (5). Fish. Newslett. (Austral.), 22(3) : 20 ; 22(5) : 21, 27 ; and 22(7) : 19, 27.

MUIR, A. T. 1959. Guide to "Canada Inspected" standards. Part 1. Plant construction - floors ; walls ; ceilings ; ventilation ; lighting. Canadian Fisherman, 46(9) : 20-22, 27-30. 1959. Guide to "Canada Inspected" standards. Part 3. What you should know about processing equipment. Ibid., 46(111 : 19-22, 27-30. 1959. Guide to "Canada Inspected" standards. Part 4. Sanitation and fish processing machinery. Ibid., 46(12) : 29-35. 1960. Guide to "Canada Inspected" standards. Part 8. Some developments in refriger­ ated transportation. Ibid., 47(4) : 19-26.

MUIR, ALLAN T., AND lAIN C. S. MACNAB. 1960. Packages and packaging materials. Ibid., 47(3) : 21-25.

NICOL, D. L. 1958. Some problems of transient-state conduction in the cooling of fish fillets. J. Sci. Food Agr., 9: 78-82. 1960. New type of smoke generator. Food Mfr., 35: 417-419.

OKADA, MINORU. 1961. Fish sausage in Japan. FAO Conference on Fish in Nutrition, Washington, Sept. 19-27, Working Papers, Vol. 1, Paper No. C/ll/9.

PATASHNIK, MAX. 1963. Net-weight determination for frozen glazed fish. Comm. Fish. Rev., 25(10) : 1-5.

PETERS, JOHN A. 1960. Packing of fishery products. Fishing Gazette, Annual Review, 77(1 3) : 148.

43 PISKAREV, A., AND S. GAKICHKO. 1957. The basis of fish glazing. Food Sci. Abstr. , 29(6) : 523. (Abstr. 2164) .

POTTINGER, S. R., AND DAVID T. MIYAUCHI. 1956. Protective coverings for frozen fish. Sect. 3, U. S. Fish and Wild!. Servo Fish. LeaH., 429, pp. 47-50.

PRATER, A. R., AND W. A. MONTGOMERY. 1963. Fish preservation inquiries. III. Fisheries products. Fish sausages (2) and (4) . Fish. Newslett. (Austral.), 22(4) : 25-26 ; and 22(7) : 19, 27.

REAY, G. A., AND J. M. SHEWAN. 1949. The care of the trawler's fish. Dept. Sci. Ind Res.,. Aberdeen, Food Investigation Leaflet No. 3.

REUTER, H. 1949. Progress in the production of fish sausages (Fortschritte in der fischwurst­ produktion). Die Fisch-Woche, 4(26) : 365, 2 pp. (in German) .

RIETZ, CARL A. 1961. A guide to the selection, combination and cooking of fo ods. A VI Publishing Co. Inc., Westport , Conn., 395 pp.

SCHMIDT, P. J. 1948. Analyses of freshwater fishfr om Canadian interior provinces. Fish. Res. Bd. Canada, Pac. Prog. Rep. No. 75, pp. 48-51.

SCHOONENS, J. G. 1950. Fish sausages have a future (Visworstjes hebben toekomst). Vis­ serijwereld, 9(49) : 1145, 2 pp. (in Dutch) .

SCHULTZ, H. W. 1960 . Food enzymes. AVI Publishing Co. Inc., Westport, Conn., 144 pp.

SIDAWAY, E. P. 1944. The preparation of marinated herring. Fish. Res. Bd. Canada, Pacific Prog. Rep ., No. 58, pp. 20-22. 1945. Fish pastes. Ibid., No. 63, pp. 38-40.

SIDAWAY, E. P., AND O. C. YOUNG. 1943. An air-conditioned tunnel for processing fish. Ibid., No. 56, pp. 4-5.

STANSBY, MAURICE E. 1954. Composition of certain species of freshwater fish. 1. Introduc­ tion : the determination of the variation of composition of fish. Food Res., 19(2) : 231-234. (ed.) 1963. Industrial fishery technology. Reinhold Publishing Corp., New York. 393 pp.

STEVENS, H. P., AND R. F. ELLIS. 1960. Can coatings now tailor- made for top pro duct protec­ tion. Canadian Packaging, 1�(8) : 46-47 .

SUNDERLAND, P. A. 1 938. Spiced surf smelts. Fish. Res. Bd. Canada, Pac. Prog. Rep. No. 37, pp. 17-18.

1939. Chum salmon products . Ibid., No. 42, pp. 10-12.

1940. Halibut "cheeks" canned in jelly. I bid . , No. 45, pp. 4-6.

TANIKAWA , ElICH!. 1964. Fish sausage and ham industry in Japan, pp. 367-424. In Advances in food research. Vol. 12. Academic Press Inc., New York.

TARR, H. L. A. 1960. Effects of processing on fish products, pp. 283-304. In Nutritional evaluation of food processing. John Wiley & Sons, Inc., New York.

TARR, H. L. A., AND A. W. LANTZ. 1949. The effect of mechanical washing of fish on the keeping quality of fillets prepared from them. Fish. Res. Bd. Canada , Pacific Prog. Rep. No. 81, pp. 80-83.

TARR, H. L. A., A. W. LANTZ, AND NEAL M. CARTER. 1950. The preparation and applica­ tion of brines and dipping solutions for processing certain fish products. Fish. Res. Bd. Canada, Pacific Prog. Rep. No. 84, pp. 51-57.

THURSTON, CLAUDE E. 1958. Sodium and potassium content of 34 species of fish. J. Am. Diet . Assoc., 34 : 396-399.

44 freezing preservation of fo ods. Westport , Conn. 1214 pp,

of preservable Food Hygienic Soc. Japan, :1(3).

industry in Japan. Kureha Chemical Industry Co., Ltd., General Food Tokyo, Japan. 12 pp.

U, INTERIOR, FISH AND WILDLiFE SERVICE, 1951. Composition of fre:;hwater fish, Comm. Fish, Rev., 1 3(12) : 13-14. 952. Composition of freshwater fish. Ibid., H( 1) : ] 7; 14(2) : 30 ; 14(3) : 22 ; 14(5) : 13 ; ; 14 (9) ; 20 ; 14 ( 10) : 27 ; H(ll) . ; 1:1(12) : 15. Composilion freshwater fish. Ibid., 15(2) : 30; 15 (4) . 17; 15( 10) : 17-18; 15(12) :

of freshwater fish. Ibid., 16(5) : 21. 1954. CoJd.,stowge lifeof fresh-water fish 1. 16(9) . 18-20. 1955. Cold-storage life of fresh-water fish - No. Ibid . 17(11) : 19-21. 1955. Technoiogical research on the fresh-water fisheries ofthe U. S. Ibid., 17(10) : 31-34. 1962. and sausage quality standards (ill Jc:pan). Ibid., 2t(5) : 61-62.

:J. OF AGRICULTURE. (Undated.) Food the ye:lfbook of agriculture 1959. Superintendent Washington, D. C. 736 pp.

. DOTY, L. J. PIRCON, AND G. WILSON. 1961. Am. Meat InsL Found., Chicago, Bull. "No. 47, 16 pp.

HARRY Practical fo od microbiology technology. A VI Publishing Co. Westport, Conn., 345 pp.

Y�OUNG , Ed. No. 35, pp. 18-22. Refr. J., W(ll) : 21 -22, 1962. handling and processing Canadian Food Ind., :-I;H8) '

45