참조기의 품질지표 개발을 위한 생산 시기별 영양성분 분석과 신선도 평가

Abstract

The yellow croaker (Larimichthys polyactis) is a widely consumed finfish in Korea. In the fishery auction market, the yellow croakers are categorized based on length and weight measurements, but no scientific evidence supports these evaluations. Moreover, the freshness of the seafood directly influences its quality, given its perishable nature, which impacts both its flavor and texture. Hence, this study aimed to establish a scientific and objective quality index for yellow croakers and to provide fundamental data for regulating its freshness during the distribution. Yellow croakers were purchased during January, August, September, October, November, and December 2022 at the Mokpo fishery auction market. The samples were subsequently classified and analyzed into six groups based on weight and the major food components (crude protein, crude fat, free amino acids, and fatty acids). In order to determine a factor to indicate the food quality of yellow croaker, a correlation analysis was conducted between the food components and weight. The correlation analysis between the food components and weight revealed that docosahexaenoic acid (DHA) content exhibited the highest significant correlation, with a correlation coefficient of 0.415 (p<0.01). Furthermore, yellow croakers were stored under three different temperature conditions (4℃, 10℃, and 15℃) for freshness analysis. Various factors were analyzed, including viable cell counts, coliforms, volatile basic nitrogen (VBN), trimethylamine (TMA), and sensory evaluation. The results demonstrated that all freshness factors increased over the storage period. Regression analysis of each freshness factor indicated that the VBN has a high coefficient of determination (0.9032-0.9421). Consequently, VBN contents showed the most significant linear relationship with freshness. Using the VBN regression equation, the shelf-life at 4℃, 10℃, and 15℃ was determined to be 7.06, 5.44, and 2.56 days, respectively. Finally, this study identified a strong link between DHA contents as a nutrition component and weight. As a result, the DHA content of yellow croaker will be beneficial as a food quality index. Furthermore, freshness is an important food quality measure for finfish. Consequently, the yellow croaker freshness index proposed in this work will be valuable in successfully managing the freshness of finfish by anticipating its shelf-life throughout distribution.