Abstract
The effects of gamma irradiation on changes of chemical compounds of fermented shromp with low salt were studied. The shirmp was salted NaCl concentration of 10%, 15% and 20%, and irradiated at 0, 2.5, 5.0, 7.5 and 10.0kGy. Amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA) and neutral protease acivity were examined during ferentation at 15$^{\circ}C$. A sample with 30% salt concontration was also prepared as a control. The initial contents of AAN, VBN, TMA and protease acitivity were not affected by gamma irradiation. The contents of AN, VBN and TMA were incteased with fermentation period. But, the more increased NaCl concentrations and the higher irradiation dose, the loss increased content of chemical compounds and protease activity were found. Protease was increased until 4~5 weeks and then decreased gradually. The results showed that the chemical compounds and protease activity of salted abd fermeted shrimp prepared with 15% NaCl contentration and 10 kGy irradiation dose, or 20% and 5 kGy or higher were maintained the appropriate level of quality up to 10 weeks of storage compared with the control.
저 염 세우젓을 제조하기 위하여 식염농도를 각각 10%, 15% 및 20%로 조절한 새우젓에 감마 선을 조사한 후 15$^{\circ}C$에서 발효시키면서 아미노태 질소, 휘발성 염기태 질소, trimethylamine 및 단백질분해효소의 할성변화를 조사하였다. 감마선 조사직후 아미노태 질소, 휘발성 염기 태 질소, trimethylamine 함량 및 단백질 분해효소 활성은 감마선 조사에 의해 영향을 받지 않는 것으로 나타났다. 발효기간 동안 아미노태 질소, 휘발성 염기태 질소 및 trimethylamine 함량은 증가하였으나, 효소활성은 발효 4~5주까지 계속 증가하다가 점차 감소하는 경향을 보였다. 특히 15% 식염첨가와 10kGy의 감마선 조사 및 20% 식염첨가와 5~7.5kGy 이상의 감마선 조사를 병용처리한 새우젓의 경우, 30% 식염성 염기태 질소, trimethylamine 함량 및 단백질분해효소 활성이 비슷한 수준으로 발혀기간 동안 적정 수준 의 함량 및 활성을 나타내었다.
