51A-21

K. T. HWANG, Dept. of Food Science and Human Nutrition, Chonbuk National University, College of Home Economics, Chonju, Chonbuk, 561-756, South Korea, J. S. Hong, and S. T. Jung, Dept. of Food Engineering, and Food Industrial Technology Research Center, Mokpo National University, Muan, Chonnam, 534-729, South Korea.

JUSTIFICATION: Catfish has been cooked in a regular manner. Besides, it has been considered as a highly nutritious commodity in Korea. Thus, they have traditionally made a kind of extract by boiling the whole fish and various herbs thoroughly. Since the fish is high in lipids and they are highly unsaturated, it must be the first step to analyze fatty acid composition of lipids from the whole fish as well as the flesh only.

OBJECTIVE: The objective of the study was to analyze and compare the fatty acid compositions of lipids in whole body and flesh of catfish.

METHODS: Live catfish was caught at a catfish farm or purchased from market in April, September, October, and November in Korea. The whole body or flesh of the fish was minced. Fat was extracted with chloroform-methanol-water. The fat was methylated using methanolic NaOH and BF₃-methanol reagent. Methylated fatty acids were analyzed with GC.

RESULTS: The fat contents of the catfish ranged from 6.7% to 9.2% for the whole fish and from 5.2% to 7.2% for the flesh with seasonal variation. The fat content in the fish caught in April was the highest among the tested ones and that in September was the lowest. However, there was some difference between the whole fish and the flesh. Pamitoleic, linoleic, and docosahexaenoic acids were more detected in the lipids from the whole fish (8.4, 13.1, and 5.2%, respectively) than the flesh only (7.8, 2.8, and 4.1%) while stearic, oleic, and eicosenoic acids were lower in the whole fish (3.3, 27.2, and 3.3%, respectively) than the flesh (4.4, 32.1, and 3.7%). Myristic, palmic, linolenic, and eicosapentaenoic acids were almost the same (about 2.2, 16.2, 1.1, and 2.9%, respectively).

SIGNIFICANCE: Catfish can be a good source of polyunsaturated fatty acids including EPA and DHA, especially using the whole fish.