Abstract

The change of cell counts of Vibrio vulnificus in meat homogenates of fish and shellfish by the storage time and temperature was examined to get basic information for precautionary steps against septicemia from slices of raw fish (sashimi). Therefore, we inoculated raw and cooked meat homogenates of fish and shellfish with Vibrio vulificus M-8 (isolated from shellfish ) and stored them at $-20^{\circ}C,\;4^{\circ}C\;and\;30^{\circ}C$ for 72 hours. Vibrio vulnificus M-8 was not detected in 32 hours when it was frozen and stored at $-20^{\circ}C$ after inoculating them into phosphate buffer solution at concentration of $10^5\;cell/ml$, while the existance of Vibrio vulnificus was identified after 72 hours of storage at the same temperature in case of inoculation into the meat homogenate of yellow tail. The cell count of Vibrio vulnificus was decreased as about $20\%$ of initial count after 2 hours storage at $4^{\circ}C$ in phosphate buffer solution with fish and shellfish homgenates. From the experimental results it was recognized that Vibrio vulnificus was labile to the cold stress. In comparison to the growth of growth of Vibrio M-8 at $30^{\circ}C$ in the raw and cooked meat of the yellow tail(Seriola guingueradita), snapper(Chrysophrys major), ark shell(Anadra brouhgtonii), and oyster(Crassostrea gigas), the raw meat homogenates were more excellent than the cooked ones though all fish and shellfish meat homogenates were proves to be good for the growth of the microbe.

방어, 참돔, 피조개, 굴 4종의 어패육에 V. vulnificus M-8을 접종하여 저장온도와 시간에 따른 균수의 변화를 시험한 결과는 다음과 같다. 1. V. vulnificus의 저온저항성은 $-20^{\circ}C$의 $1.5\%$ 식염-인산완충희석수에서는 32시간에 거의 사멸하였으며, 방어육 균질액에서는 인산완충희석수에서 보다 감소가 완만하였고 72시간 이후에도 균이 검출되었다. 그리고 $4^{\circ}C$ 저장에서도 균의 감소가 현저하였다. 따라서 이 균의 저온저항성은 약하지만 단시간 냉동 및 냉장에 의한 균의 사멸은 어렵다는 것을 알 수 있었다. 2. 어패육에 접종하여 $30^{\circ}C$에 저장한 시료중의 V. vulnificus의 증식은 일반적으로 16시간만에 최대균수에 달하였으나 피조개의 경우는 12시간으로 약간 빨랐으며 특히 방어육에 있어서는 초기에 감소하는 특징과 더불어 균의 증식속도가 완만하였다. 그리고 가열처리육보다 생육에서의 균의 증식이 빠르게 나타났다.

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