Quality Test of the Sweet-and-Sour Porks and Deep-Frying Oil from the Chinese Restaurants in Seoul

서울 지역 중화 요리점의 탕수육 및 튀김유의 품질 측정

  • Kim, Hyo-Jin (Dept. of Food Science and Technology, Chungnam National University) ;
  • Xue, Chenglian (Dept. of Food Science and Technology, Chungnam National University) ;
  • Lee, Ki-Teak (Dept. of Food Science and Technology, Chungnam National University)
  • Received : 2010.05.10
  • Accepted : 2010.08.02
  • Published : 2010.08.31

Abstract

In this study, we determined the fat content, total fatty acid composition, trans fatty acid (tFA) content, and acid value of twenty samples of sweet-and-sour pork and fifteen samples of used frying oils collected from Chinese restaurants in Seoul. After the extraction of crude fat by the Folch method, the total fat content of the twenty sweet-and-sour porks ranged from 9.93 to 20.04%. The total unsaturated fatty acid content ranged from 50.05 to 81.22%, which mostly consisted of oleic and linoleic acid, while those of total saturated fatty acids were 18.06~49.26%. The tFA content of all of the twenty sweet-and-sour porks tested was less than 0.24 g per 100 g of food. The acid values of the fat extracted from the twenty sweet-and-sour porks ranged from 0.44 to 4.37. In the used frying oils, the ranges of the major compositional fatty acids were as follows: palmitic acid, 4.47~20.28%; oleic acid, 23.43~77.45%; linoleic acid, 5.6~53.06%; stearic acid, 1.81~7.38%. The tFA content in all of the fifteen used frying oils was less than 0.98 g per 100 g of fat, while the acid values of the fifteen used frying oils ranged from 0.27 to 2.41.

본 연구는 서울 지역 중화 요리점들로부터 탕수육과 튀김유를 각각 수거하여 지방 함량과 지방산 조성, 트랜스 지방산 함량 및 산가를 비교 분석한 후 탕수육 및 튀김유의 품질을 측정하였다. 탕수육 20종 시료의 총 지방 함량은 평균 14.65%로 측정되었으며, 주요 지방산은 평균적으로 linoleic acid($C_{18:2}$)는 38.13%, oleic acid($C_{18:1}$)는 30.07%, palmitic acid ($C_{16:0}$)는 17.14%의 순으로 높은 함량을 차지하였다. 총 불포화지방산은 평균 70.79%, 포화지방산은 평균 23.47%로 측정되었다. 탕수육 시료 중 6번, 7번, 9번, 16번, 17번 시료를 제외하고 linoleic acid, oleic acid, stearic acid의 순으로 많았으며, 이 세 개의 지방산이 85.38~87.27%를 점유하였다. 반면에, 7번, 9번 시료의 지방산 조성을 살펴보면 oleic acid(평균 41.88%), palmitic acid(평균 23.46%), linoleic acid(평균 15.22%) 순으로 높은 함량을 나타냈으며, 16번, 17번 시료의 지방산 조성을 살펴보면 oleic acid(평균 34.83%), linoleic acid(평균 28.68%), palmitic acid(평균 20.21%)의 순으로 높은 함량을 나타냈다. 특히, 6번 시료는 palmitic acid가 40.70%로 높게 함유하고 있었으며, 총 포화지방산 함량은 49.26%, 총 불포화지방산 함량은 50.05%를 나타내었다. 15종의 튀김유의 주요 지방산 조성을 분석한 결과, palmitic acid는 11.65~20.28%, oleic acid는 23.54~26.32%, linoleic acid는 43.82~52.55%, stearic acid는 3.98~5.29%로 주로 구성되어 있었으며, 탕수육 시료와 튀김유 각 100 g당 함유되어 있는 트랜스 지방산의 함량은 0.24 g와 0.98 g 이하로 각각 적은 양을 함유하고 있었다. 또한, 모든 시료는 식품공전상 튀김유의 산가 규격을 초과하지 않는 것으로 나타났다.

Keywords

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