Relationship between processing techniques and the amount of vitamins and minerals in processed fish
Higashi, H. (1962). Relationship between processing techniques and the amount of vitamins and minerals in processed fish, in: Heen, E. et al. Fish in nutrition. pp. 125-131
In: Heen, E.; Kreuzer, R. (1962). Fish in nutrition. Fishing News (Books): London. XXIII, 447 pp., more
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Abstract |
Fish is a rich source of vitamins and minerals for both man and domestic animals. The amounts of these nutritive substances contained in fish, however,vary according to biological factors such as species, age, and the anatomical part of the fish. Moreover, processing techniques affect the stability level of vitamins. It is therefore necessary to determine the extent of loss of vitamins in fish from an initial level for each processing technique. As a raw material for human consumption, an individual fish may roughly be divided into edible and non-edible parts, the latter usually being discarded before cooking. In a large-sized fish, for instance, the non-edible portion may include the head, fins, viscera, bones and scales. It has been shown, however, that many of the vitamins and minerals of nutritive value are more abundant in the non-edible portion. Furthermore, vitamins and minerals in the edible part are not always very constant in quantity, varying according to the different parts of the fish body. Therefore, a processing technique may often exert an effect upon the amount of the nutritive elements in a product, even when only the edible portion is used. In fresh fish, nearly all vitamins are found in the edible portion, though the level of concentration differs with the species. Generally speaking, however, most of the fat-soluble vitamins do not present a significant loss in quantity during processing. It is during storage that salted or frozen products show a considerable loss in vitamins due to oxidation. The use of an antioxidant is a very effective preventative, unless the oil contents in fish are large. Then the use of an antioxidant may sometimes prove uneconomical. Water-soluble vitamins in fish may sometimes be lost through decomposition by heating, or in extraction by water or a salt solution. Nevertheless, this characteristic can be turned to advantage by enhancing the nutritive value of fish solubles in food for domestic animals by collecting water-soluble vitamins as much as possible from the raw material. In Japan, where the consumption of fish as food is the highest in the world, there are many processing techniques, and there is great interest in biochemical changes in vitamins and minerals during processing. Some of the studies made concerning processing factors responsible for changes in these nutritive elements of fish are described in this paper. |
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