EVALUATION OF SOME NUTRITIVE VALUES AND ORGANOLEPTIC QUALITIES OF COOKED FRESH AND FROZEN MALE FORMATTED (MONO-SEX) BOLTI FISH.

This work was aimed to study the effect of home cooking processes and frozen storage (at -20°C for 6 months) on the chemical composition, digestibility and quality of common and male formatted (mono-sex) Bolti fish flesh. The results indicated that crude protein and ether extract were higher in male formatted than the common Bolti fish flesh. Crude protein, ether extract and ash of the flesh were decreased after cooking processes. The lowest loss in protein was found in roasted fish. After frozen storage for 6 months at -20°C, the gross chemical composition of frozen fish were lower than those of fresh fish. The total indispensable amino acids (35.74%) especially theronine, methionine, valine, phenylalanine, isoleucine and tryptophan were higher in fresh male formatted Bolti fish flesh than those in fresh common fish flesh (33.51%). The total amino acids were decreased in all fish samples as result of cooking processes and frozen storage. The lowest losses in amino acids were noticed in fried samples. The results revealed that male formatted fish contained higher amounts of total unsaturated fatty acids (67.67%) than those of common fish (62.62%), especially oleic, linoleic and erucic acids. The fatty acids compositions of fresh samples were changed after cooking processes. Frying process increased oleic, linoleic and linolenic acids of both types of fish. Erucic acid was not found in fresh after frying process. Great decreases were noticed in linoleic acid content of fish after 6 months of storage at -20°C from 16.82 to 7.63% and from 20.16 to 19.46% for common and male formatted fish, respectively. Arachidic, behenic and erucic acids were disappeared after frying and wet cooking of frozen two fish types. Also, arachidic, behenic and erucic acids were not found after roasting of  male formatted fish samples. The results indicated that, male formatted Bolti fish had higher digestibility values than common fish. Cooking processes and frozen storage of the two fish types reduce the digestibility values, but male formatted fish still had higher digestibility values. Cooked male formatted fishes treated had better over all acceptability values than those of common Bolti fish samples.