Abstract
The nutritional characteristics of a semi-fermented fish product, commonly known as chapa shutki in Bangladesh, were studied. Its crude protein, crude fat, and crude ash contents were 33.2, 17.0 and 12.2 %, respectively. The calcium, phosphorus, magnesium and iron contents of chapa shutki were higher than those of similar kinds of Japanese processed fish. The amino acid score of the protein was found to be 100, based on the provisional amino acid scoring pattern (FAO/WHO 1990). The percentage of available lysine was 97.6. Chemical changes in the amino acid residues scarcely occurred during processing. Palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acids were the major fatty acids of chapa shutki. Highly unsaturated fatty acids with 20 or more carbons were relatively low. No significant losses of unsaturated fatty acids were observed during the semi-fermentation process. An investigation of the extent of lipid oxidation showed that the carbonyl value and thiobarbituric acid-reactive substances value were 27 meq/kg of oil and 38 mg/kg of oil, respectively. The level of peroxidation was the very minimum. These feature indicite that chapa shutki can be considered a high-quality protein food.
