High Hydrostatic Pressure Sterilization of Putrefactive Bacteria in Salted and Fermented Shrimp with Different Salt Content

염농도가 다른 새우젓에 존재하는 유해가능 세균의 초고압 살균

  • Mok, Chul-Kyoon (Department of Food and Bioengineering, Kyungwon University) ;
  • Song, Ki-Tae (Department of Food and Bioengineering, Kyungwon University)
  • 목철균 (경원대학교 공과대학 식품생물공학과) ;
  • 송기태 (경원대학교 공과대학 식품생물공학과)
  • Published : 2000.06.30

Abstract

This study was conducted to enhance the storage stability and the wholesomeness of salted and fermented shrimp manufactured with different salt levels by high hydrostatic pressure sterilization. The effects of high hydrostatic pressure treatment on the putrefactive bacteria in the fermented shrimps were investigated and the sterilization kinetics was analyzed. The initial microbial counts of the fermented shrimp with 8%, 18% salt aged for 6 weeks at $20^{circ}C$ were $1.6{\times}10^3,\;1.4{\times}10^4$ CFU/g for bacteria grown on Vibrio selective media, $9.3{\times}10^3,\;1.7{\times}10^5$ CFU/g for bacteria grown on Staphylococcus selective media, respectively, and null for bacteria grown on Salmonella selective media. The degree of the sterilization increased with the magnitude of the pressure and the treatment time. The fermented shrimp pressurized at 6,500 atm for 10 min had no detectable bacteria grown on Vibrio and Staphylococcus selective media at $10^2$ CFU/g detecting limit. High hydrostatic pressure sterilization could be analyzed by first order reaction kinetics. The $D_P$ values of the bacteria grown on Vibrio selective media of the fermented shrimp at 18% salt were higher than those at 8% salt, while those of the bacteria grown on Staphylococcus selective media showed an inverse trend. The $z_p$ values of 8% salt fermented shrimp were higher than those of 18% salt for both bacteria grown on Vibrio selective media and Staphylococcus selective media. High hydrostatic pressure treatment could be applied for the sterilization of the fermented shrimp, and the optimum high pressure sterilization condition was 10 min treatment at 6,500 atm.