The Effect of Antioxidants on the Fermented Sardine and Taste Compounds of Product

정어리젓 가공에 있어서의 항산화제 처리 효과 및 제품의 정미성분

For the effective utilization of sardine, sardinops melanosticta, one of the major coastal fish in Korea, of which annual catch has been increasing from year to year since 1970, it was processed in form of fermented fish paste. The fish were treated with BHA and Teaox-Ⅱ in concentration of $0.01\%\;and\;0.02\%$ to prevent the oxidation of lipid during fermentation and then salted with $20\%$ table salt and fermented at room temperature of $25\pm3^{\circ}C$. The duration of fermentation necessary for the final product with an acceptable taste was determined by sensory evaluation by means of profile method. From the result of sensory evaluation, one month was found to be suitable as the reasonable duration of fermentation. Both BHA and Tenox-Ⅱ in conceatration of $0.02\%$showed a good preventing effect on the lipid oxidation during fermentation. In case of fermented sardine treated with both antioxidants, lipid oxidation occurred little up to two months, whereas the control showed a remarkable deterioration during one month of fermentation. Most of the nucleotides in sardine was decomposed from adenosing triphosphate to inosine and hypoxanthine during the fermentation of one month. The great portion of free amino acids in the extractives of product was occupied by leucine, glutamic acid, isoleucine, alanine, valine and ysine in turn, and their coatent was $59.4\%$ of the total free amino acids. The amount of essential amino acids was $59.4\%$ of the total free amino acids. The contents of 5'-IMP, betaine, trimethylamine oxide and total creatinine in the extractives of product were $1.9{\mu}mole/g,\;4.9mg\%,\;1.0mg\%\;and\;475mg\%$, respectively. According to the omission test, the main constituents of the characteristic taste of fermented sardine could be assumed as free amino acids and a little amount of 5'-IMP.

항산화제처리가 정어리젓 숙성 중의 지질의 산패방지에 미치는 효과 및 정어리젓의 정미성분을 분석하였다. 정어리젓을 실온($25\pm3^{\circ}C$)에서 숙성시켰을 때, 대조구는 숙성 31일째까지 지질의 산화가 급속히 진행되었으나 BHA 및 Tenox-Ⅱ를 처리한 것은 모두 지질의 산패방지 효과가 있었다. 항산화제 처리농도는 BHA, Tenox-Ⅱ 모두 $0.01\%$ 첨가한 것보다 $0.02\%$ 첨가한 것이 더욱 효과가 좋았다. ATP 관련물질은 숙성 31일만에 거의 inosine 및 hypoxanthine으로 분해되었다. 그리고, 유리아미노산 중 함량이 많은 것은 leucine, glutamic acid, isoleucine, alanine, valine 및 Iysine으로서 전유리아미노산에 대하여 $59.4\%$를 차지하였다. 특히 lysine이 $7.2\%$나 함유되어 있어 영양학적 의의가 크다고 생각된다. 정어리젓 중의 5'-IMP, betaine, TMAO 및 충 creatinine 등은 엑스분에 대하여 $1.0\%$, $0.02\%$ 및 $10.8\%$로서 비교적 적은 양이지만 유리아미노산과 함께 정어리젓의 맛에 보조적인 구실을 할 것이라고 추정된다.