تاثير مدة التجميد المنزلي في بعض الخواص الكيميائية و الحسية لبعض انواع السماك الساحل السوري

Five Species of the most widely consumed fish in the Syrian Coast (namely Merluccius merluccius, Diplodus sargus, Siganus luridus, Lithognathus mormyrus, and Chelon labrosus). were selected for this research. Samples were collected from the fish market in lattakia, with weight ranging between 150 and 200g. Samples were cleaned by removing scales and inner organs, freezed at -35°C for five hours and then stored at -18°C for a maximum period of six months. Chemical analysis of fish samples was carried out before and after freezing periods of one week, 1, 2, 4 and 6 months. Analysis included determination of moisture, proteins, lipids, acidity, volatile nitrogen, and peroxide value. Organoleptic evaluation was also performed on the control (fresh samples) and on the frozen samples after thawing and frying. The evaluation included taste, flavor, color, texture or meat consistency and form homogeneity. The results of the chemical analysis showed a decrease in moisture content and an increase in acidity, volatile nitrogen and peroxide values of all samples in proportion to the duration of storage. Organoleptic evaluation of the fried samples indicated deterioration of the studied quality characteristics, especially taste and flavor and meat consistency which was also proportional to the duration of storage. The deterioration was more obvious in the two species Gharibah and Merlan so that it limited the period of their storage to one week compared to two months for the other four species of fish. The fast deterioration in Gharibah and Merlan species during frozen storage may due to their higher content of lipids than the other species.