Fish protein is incorporated into the human diet not only via the visible direct consumption of fish flesh, fresh or preserved. In many parts of the world more sophisticated fish products or elaborate fish dishes have emerged. Several of these are important outlets for fish protein or its amino acids. The fermented items so commonly encountered and used in the entire Southeast Asian region are reviewed in Volume III, Chapter 20.
Fish macaroni is one such product devised by Indian scientists for home-cottage production or large-scale industrial manufacture.
French nutritionists have concocted a special biscuit containing several proteins from corn, groundnuts (peanuts), dry milk, dried yeast, and coconut. Moroccan fish flour has no other ingredient (Mauron et al., 1960). Fish is the major source of lysine in this special type of flour, and, together with milk, it provides most of the methionine. This combined product maintains its lysine content both in storage and manufacturing better than the individual ingredients do when treated in the same way.
298 GEORG BORGSTROM a. FISH MEAL
It is deplorable that fish meal, at the present time, is not wholly con
verted into direct use as human food. This is primarily due to technical reasons. Furthermore, there is heavy competition between the domestic animals of the well-fed parts of the world and human beings in these developing areas. Agriculture is given almost entire credit for the flourisliing postwar animal production of Europe. This is only partly justified—a major factor is the channeling of animal protein through the back door via fisheries. Few realize that several major European countries feed more fish protein to their domestic animals than they do to the human beings. This is true for Denmark, West Germany, the Netherlands, Norway, and the United Kingdom. It is most surprising to find in this same category South Africa, a country where a large portion of the population is seriously short of protein.
The United States is, next to Peru, the largest producer of fish meal, but is nevertheless buying on the world market more fish meal and fish solubles than any other country. In terms of protein, this importation amounts to approximately one-seventh of what currently is totally consumed in meat and as much as two-thirds of what is available as poultry meat! No less than approximately one-third of the United States broiler meat production can in effect be attributed to the sea. Half of this marine feed is imported. The United States constitutes the major market for world fish meal, surpassed only by Europe when all individual countries there are added together.
This United States purchase of protein could, in fact, satisfactorily fill the protein gap of the highly protein-deficient South American continent (Borgstrom, 1958). A channeling of the fish protein now used as feed for domestic animals into human use could appreciably improve the poor protein standard in many regions and indirectly enhance productivity. Great importance consequently must be attached to the present efforts toward improving and expanding the manufacture of fish flour which can be used as a supplement in breads, soups, puddings, etc. Undoubtedly such fish protein would constitute an excellent basis for world-wide relief.
This protein deficit is worth observing in discussing economic balance and surplus problems. On the basis of the experience of Japan and most European countries, it is correct to assume that agriculture in Latin America would hardly be able to provide sufficient protein to feed the rapidly growing population, particularly if the nutritional standard is going to be improved in those many countries which now live on a substandard level in this respect. Fish will not only be cheapest but also the most efficient way of ameliorating present conditions. This
7. FISH IN WORLD NUTRITION 299 explains the great interest which today is attached to development of the fishery resources of Latin America. Surveys of the Caribbean area, however, clearly point to definite limitations. This presumably will always be a deficit area where cheaper protein in the form of milk products or fish protein will have to be imported from other regions more favorable to protein production. Promising improvements are, however, reported from Chile, Peru, Brazil, and Venezuela. Brazil today imports almost half of the fish protein presently consumed. This explains the current efforts to utilize more effectively both the sea and fresh-water resources of this great country (Beatty, 1960). The climate, the distribution and the composition of the fish fauna, the large distances, and several additional factors explain the slow progress being made. Several good enterprises have ended in failure because of negligence of one or the other of these basic factors. Drying is by far the most preferable and cheapest method of preservation.
Research has shown that fish meal and condensed fish solubles contain substantial amounts of vitamin B12. This explains the special value of fish as a supplement to vegetarian diets. The more agricultural production is compelled, for the sake of better acre utilization, to increase further the output of plant products as a valid substitute for animal protein, the more vital does the availability of Bi 2 become to human nourishment. This puts fish and fish products in a key position. The most recent discoveries of efficient methods to isolate Bi2 from sewage wastes may, however, partly change this situation.
b. INSULIN
The whaling industry nowadays provides a substantial quantity of insulin. According to South African discoveries, the pancreas of shark also contains a very high percentage of insulin. One hundred and thirty sharks produce the same amount as is obtained from 400 to 500 cattle.
c. FERTILIZERS
To what extent fish and fish waste are used as fertilizer is difficult to establish and still more difficult to estimate is what additional food agriculture produces thanks to this source. Early in human history fish was utilized this way, in Brittany, on the minor islands of the British Isles (Aran, the Shetlands, the Hebrides), Norway, Maine, and other parts of New England.
This practice must not be overlooked, although it certainly played a far greater role in bygone periods of history when methods of utilization were less developed. Such use of herring in Scandinavia and Ireland, and salmon by New Englanders and North American Indians
300 GEORG BORGSTROM
is well documented. Nevertheless, using the fish this way had its limita
tions since the potassium level in no way matched the amounts of nitrogen and phosphate present or added. Particular importance is attached to fertilizing with salt-water fish because the iodine generally penetrates the agricultural products grown on soil fertilized in this manner.
D. FISH AND SHELLFISH AS A FAT SOURCE