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cialty products, however, can be produced from salmon on a small scale such as canned, smoked salmon. Such products would have only a limited sale and would not increase the total salmor pack by an appreciable amount yet might furnish a livelihood for several small operators. Such products are not necessarily limited to salmon. For example, a product similar to finnan haddie which should find a ready market can be produced from several West Coast fish. When canned, this product is non-perishable. Several such products have been developed by the Fish and Wildlife Service laboratories.
Various dehydrated fish products may have some limited possibility in the post-war period. Extensive experiments have been carried out by Service laboratories on dehydration of fish for wartime use. Most of such dehydrated fish is not palatable enough for domestic consumption, but a few special products may have post-war possibilities. One of these is an all-dehydrated fish chowder in which all the dried ingredients are packaged together, so that it is only necessary to add water and heat to reconstitute the chowder.
Fishery Byproducts--An enormous volume of salmon cannery trimmings are, at, present, discarded in Alaska, These trimmings contain the same protein and other nutrients that go into the canned product. Because of the isolated locations of the canneries in Alaska, the brevity of the canning season, and the great distances between canneries, it has been impracticable to utilize most of this cannery waste in the past. Owing to the perishability of the raw material and the distance between canneries, it has been impossible to erect a few centrally located reduction plants to handle waste from several plants, except in southeastern Alaska where canneries are relatively close together, The canning season extends only 4 to 8 weeks in most cases, and the cost of reduction equipment is too great for economical operation during this short period.
Laboratories of both Fish and Wildlife Service and those of industry have been giving considerable attention to utilization of cannery wastes with the hope of developing some simplified procedure whereby it could be at least partially processed or preserved at the individual canneries, final processing then taking place at centrally-located plants. Owing to the complexity of the problem and its being interwoven with economic considerations, no immediate solution is in sight. However, there seems no doubt that this problem will eventually be solved, and, at that time, there will be many opportunities for new plants in Alaska to handle the large quantity of raw material now being discarded.
When the fish fillet expansion takes place, there will likewise be room for new reduction plants to take care of the increased volume of fillet waste, The Service is beginning a project to work out technical details in connection with such fillet waste reduction,
Certain pharmaceutical products are prepared from fish. The Vitamin A fish-liver field is well known, and it is probably developed to the fullest capacity that the availability of raw material permits. Other vitamins of the Vitamin B group can be obtained as a byproduct from fish reduction plants, and although a good start already has been made in this direction in California, most other areas have not given this field consideration,
Still other pharmaceutical products have been produced from fish waste. These include amino acids, enzymes, and many other similar products. This field has scarcely been touched and offers tremendous opportunity for research and development.
Before the war, most of our agar and gums which are extracted from seaweeds were imported from Japan. With this source cut off, domestic production had to be initiated to augment the limited stockpiles available. Several plants have been in production, especially in southern California. These have managed to produce enough of such materials to supply our most critical needs. However, owing to lack of availability of equipment and manpower, these plants have been able to operate only at a small portion of the capacity which would be required to satisfy all of our needs in this field. If it is found to be feasible to compete with foreign sources in the post-war period, considerable expansion in such plants will be required.
Opportunities Connected With Sport Fishing--Sport fishing in the Pacific Northwest and especially in Alaska offers innumerable opportunities for opening of fishing camps and resorts, Many service men from all sections of the country, who were stationed or trained in Washington, Oregon, and Alaska, will return home after the war with glowing reports of the sport fishing in this section. Existing resorts cannot hope to cope with the influx of sport fishermen who will visit this area after the war. While salmon and trout fishing will probably be the chief attraction, interest in sport fishing for halibut or other "groundfish" could undoubtedly be fostered, as well as for various fresh-water fishes, abundant in lakes and streams. Besides actual establishment of fishing resorts, other opportunities exist in connection with guide service required, and considerable employment should be available for local citizens well acquainted with fishing in any particular area.
With vast increases in sport fishing will come chances for establishment of small concerns for manufacture of all sorts of accessories, equipment, and bait. For example, although some salmon eggs are already being preserved for balt, most of them are discarded at present. These eggs will be available for manufacture into preserved bait when the demand increases, Returning disabled veterans might find a profitable business in the production of handmade lures. In addition, there should be an increase in the demand for all sorts of accessories such as tackle, boats, etc.
Changing population conditions in the Pacific Northwest and Alaska in the immediate post-war period are expected to change the emphasis from canned fish to a more balanced production of all kinds of products. An especially large increase will take place in the processing of fresh and frozen fillets. The changes will create many opportunities not only for expansion of existing facilities, but in the formation of new concerns. Fish and Wildlife Service fishery technological laboratories, in anticipation of these and other changes, are collecting technical information which will be available to aid the fishing industry when these changes take place,
SOME TIME AND LABOR SAVING TECHNIQUES IN VITAMIN A AND OIL ANALYSES
By F. B. Sanford, G. C. Bucher, and W. Clegs*
In the course of an extensive study of the factors affecting the potency of the dogfish liver oils, made in collaboration with the Washington State Fisheries, there were developed a number of time and labor saving techniques such as are discussed by Björksten]]. These may prove of interest to other laboratories in the oil and vitamin fields,
Use of Malted Milk Mixer--Liver homogenization has been made easy by means of a blender. However, with these machines it is difficult to handle livers weighing less than one ounce,
because the blades of the blender
Weighing Wire s--The advantage of weighing wires in handling the small quantities of oil usually employed in Vitamin A analyses has been known for some time. In this
Figure 2 Figure 1--Mixer Blades
method the coiled end of a tared Weighing Wire
wire is dipped into the oil being sampled. As it is being withdrawn, the coil is touched against the side of the container to remove the excess of oil. The weighing operation can be further simplified and made more rapid if all of the weighing wires are adjusted to exactly the same weight, which, preferably, should be an integral number of decigrams, For example, this laboratory uses *Chemists, Fishery Technological Laboratory, Seattle, Washington, 1/ Bjorksten, J., "Time and Motion Studies for Chemists," Chem. and Eng. Nows, 21, 1324 (1943)
several uozen wires which are tared to exactly 0.3000 grams and to which will adhere approximately 0.04 grams of oil. The wire used for this purpose is No. 26 chromel, approximately il inches long, formed at one end into approximately 30 coils, 1/8 inch in diameter. The other end has a single large loop by which the wire can be hung from a balance arm (Figure 2). Obviously, it is unnecessary to keep a record of the tare of the particular wire being used, and if a chain or other semi-automatic type balance is employed, the weight of the oil sample can be read directly from the dial or sliding scale. . It is a simple procedure to adjust the wire to a given weight by using wire' snips for rough adjustment and an emery wheel for fine adjustment. No change in the weight of wires used at this laboratory has been noted over a period of several months.
Paired Automatic Pipettes--The use of an automatic pipette is a substantial aid in pipetting volatile liquids such as ethyl ether. However, the rubber bulb customarily used to draw the liquid into the pipette is troublesome to manipulate. This can be overcome by using the suction afforded by a water aspirator. If two pipettes are used concurrently (Figure 3), one can be filling while the other is discharging; thus, the net time involved in the operation can be decreased by nearly one-half.
Glass Thief--Whenever it is necessary to use a quantity of oil larger than can be obtained conveniently on a weighing wire, medicine droppers are frequently employed. These, however, are somewhat difficult to clean and to manipulate. The medicine dropper can be replaced advantageously by pieces of glass tubing of about 4 mm, outside diameter--and of any desired length (Figure 4). Usually, there is sufficient oil in the sample container to fill these to the required depth by means of gravity; otherwise the tubes may be filled in the same manner as any pipette,
1 cm. Glass Thief --After liver material has been disintegrated and homogenized in a blender, a sample can be obtained easily if a glass thief i cm. in outside diameter and about 12 inches in length is used. If slightly constricted at the lower end, the thief will retain even the most oily material (Figure 5). The weight of the sample can be roughly estimated if calibration lines are etched on the side of the tube.
Tared Containers--In series of analyses in which a large number of tared containers are being used, time can be saved if the containers are numbered and tared in the order of consecutive weight. (Figures 6 and 7). Thus, in weighing these containers, only a minimum number of weights need be changed between any two weighings.
Numbering of Containerg--The identification of a sample at any stage of an analysis is simplified and the possibility of error is decreased by the use of sets of exactly 100 (or 200, etc., if more than 100 analyses are made at one time) containers of each kind required in the course of the procedure. The containers of each kind should be numbered from 1 to 100 (or 200) consecutively, so that the various containers used to handle a single
Figure 7--50 ml. Flasks
sample can all have the same number--which should correspond with the sample number itself. For example, a liver sample assigned the laboratory sample number 47, would be handled in jar number 47; after homogenization, it would be extracted in shaker bottle number 47; the oil solution would be evaporated in flask or beaker number 47; and so forth. Similarly, sample 823 would be handled in containers which are all numbered 23. Sample 899 would be placed in containers numbered 29; sample 900 in containers numbered 100; and 901 in 1; 902 in 2; etc.
COMPARABLE VALUES OF FIBERS FOR USE IN COMMERCIAL FISHERIES
By Frank E. Firth*
The commercial fishing industry was one of the first to feel the effect of the loss of imports of manila when the Japanese invaded the Philippines and East Indies. Almost immediately after war was declared, the Fish and Wildlife Service started to test those fibers which were available and might be adapted to fishing uses because there were practically no data on their comparative values as fishing cordage and twines,
The availability of fibers shifted continuously since there was no domestic production except of cotton. Uses for the latter increased at such a rate that only very small quantities of cotton rope were available for industrial uses. All other fibers had to be imported and were subject to shipping delays. In addition, the need of the Armed Forces for all types of cordage increased at a tremendous rate,
The results of the tests undertaken are summarized in the following table. Jute gave variable results depending on the use to which it was placed. This variation in performance
Comparison of Certain Cordage Fibers With Manila
Approx- Recom- AvailType
Tensile Resist- Flexi- mate
menda- ability of
bility | Durabil
Percent Manila General fisheries 100 Very good Very 100 Very None
good Java sisal General fisheries 90 Good Very 95 Very None
good Bland of Java & African sisal General fisheries
Good Very 85-90 Very Nono good
good African sisal General fisheries 80 Good
Good 80 Good Limited Blend of African sisal with 5-10% extenders of Agave- General fisheries 75 Fair to Fair 60-70 Fair Limited tow, Hene quen, Pita or
Good Very 90 Very Limited and 70% African sisal) Lobster pot head
good ing twine Jute cordage Quarter ropes,
Fairly haul-up lines,
Poor abundant tackles, lobster
pot warps Jute twine Otter trawl webbing 60 Poor
30 Poor Fairly good
abundant Jute twine
Lobster pot beads
Very 85-90 Good Fairly good
abundant Flax corda te
Lobster pot warps
good Limited Coir cordage Lobster pot warps,
Fairly Otter trawl foot- 25 Poor
20 Poor abunrope rounding
dant Cotton twine Otter trawl cod-ends 55 Poor
Good 50 Fair Limited Cotton twine Lobster pot heads 55 Good
Good 85 Very Limited
good Rapbia cordage Otter trawl hanging 60 Poor
Poor Limited lines
is due primarily to the fact that it wears out rapidly when subjected to abrasion. Some of the secondary grades of sisal cordage were handicapped by brittleness causing ropes to part without warning and give poor performance when pulled over sheaves, * Technologist, stationed at Boston, Mass.