은어의 수분 함량은 72.5%, 지방 함량은 5.3%, 회분 함량은 1.1%였다. 은어 지방 중에 단일 불포화지방산은 34.0%였다. 그중 oleic acid가 21.1%, palmitoleic acid가 7.8%였다. 다가 불포화지방산은 28.2%였는데, 그중 DHA가 12.1%, linoleic acid가 8.1%, EPA가 5.7%였다. 통째인 은어를 12일 동안 냉장($2^{circ}C$) 보관하며 TBA 값과 PV를 측정한 결과, ascorbic acid를 처리한 군과 진공포장한 군이 대조군과 비교하여 유의적인 차이가 없었다(p>0.05). FFA는 12일 동안 세 그룹간의 유의적인 차이가 없었다(p>0.05). 잘게 다진 상태의 은어를 12일 동안 냉장($2^{circ}C$) 보관하면서 TBA와 PV를 측정한 결과, ascorbic acid를 처리한 군과 진공포장한 군이 대조군에 비하여 지방산화 정도가 유의적으로 낮았다(p<0.05). 이러한 연구 결과로 볼 때, 은어가 불포화지방산과 DHA와 EPA의 좋은 급원 식품이며, ascorbic acid 처리와 진공포장이 은어 지방의 산화를 억제하는데 도움이 될 것으로 판단된다.
The purpose of the study was to determine fat contents and fatty acid compositions of the lipids in sweetfish cultured in Korea and lipid oxidation during storage at refrigeration temperature ($2^{circ}C$). Whole or minced sweetfish were vacuum-packaged or treated with ascorbic acid. Changes in thiobarbituric acid (TBA) values, peroxide values (PV) and free fatty acid (FFA) in the fish were determined. Sweetfish contained 72.5% moisture, 5.3% lipid and 1.1% ash. Palmitic acid was the highest (27.4% (w/w) of the total fatty acids) among the saturated fatty acids. Total monounsaturated fatty acids (MUFA) were 33.9% and oleic acid (21.0%) was the highest, followed by palmitoleic acid (7.8%). Total PUFA were 28.2%. Predominant PUFA were linoleic acid (8.1%), EPA (5.7%) and DHA (12.1%). TBA values and PV of the whole sweetfish treated with ascorbic acid and vacuumpackaged were not different from the control. TBA values of the minced sweetfish treated with ascorbic acid were significantly lower than the other groups (p<0.05). PV of the fish treated with ascorbic acid and vacuum packaging were significantly lower than the other groups (p<0.05). The result of this study suggests that cultured Korean sweetfish may be a good source of unsaturated fatty acids including EPA and DHA, and vacuum packaging and addition of ascorbic acid may protect lipids from oxidation.
