Changes during Storage of Rice Germ Oil and Its Fatty Acid Composition

쌀눈 유지의 저장중 변화와 지방산 구성

  • Published : 1998.02.01

Abstract

Rice germ oils were extracted from common and dried rice germ $(80^{\circ}C,\;6\;hr)$, and their oxidative stabilities were evaluated by measuring acid value, peroxide value and fatty acid composition during storage at $40^{\circ}C\;and\;60^{\circ}C$. The acid values of all lipids were slightly changed during storage, but peroxide values (POV) were greatly dependent on storage temperature. The POVs of the dried germ oil and the refined rice bran oil were 146.2 meq/kg and 15.1 meq/kg, respectively after 31 days storage at $40^{\circ}C$. However after 24 days of storage at $60^{\circ}C$, the POVs of the dried germ oil and the refined rice bran oil were 151.7 meq/kg oil and 219.6 meq/kg oil, respectively. Major fatty acids were linoleic (39.8%) and oleic acid (34.7%) in rice germ oil, and oleic (40.1%) and linoleic acid (38.1%) in rice bran oil. The major fatty acid compositions were not greatly influenced by drying and storage temperature but linoleic acid decreased about half during storage.

쌀눈 및 쌀겨에 함유된 유지를 추출, 온도별 저장 안정성과 지방산조성을 비교하였다. 쌀눈 및 쌀겨유지를 $40^{\circ}C$$60^{\circ}C$에 31일간 저장 중 유지의 산가는 큰 차이가 없었고 과산화물가는 저장 온도가 높아짐에 따라 크게 상승하였는데, $40^{\circ}C$저장 31일에는 건조처리한 쌀눈의 유지가 가장 높아 146.2 meq/kg이었고 정제유는 15.1 meq/kg 이었으며, $60^{\circ}C$저장 24일에는 정제유는 219.6 meq/kg, 건조쌀눈유지는 151.7meq/kg 이었다. 쌀눈과 쌀겨유지 중 주 지방산은 쌀눈은 linoleic acid (39.0%)와 oleic acid (34.7%)이었고 쌀겨는 oleic acid (40.1%)와 linoleic acid (38.1%)였으며, 저장 중 주 지방산의 조성은 쌀눈의 건조처리나 저장온도에 큰 영향을 받지 않았으나 linolenic acid의 함량은 모든 처리에서 감소하는 경향이었다.

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