Survival of Pathogenic Yersinia enterocolitica in Vacuum-packed or Non-vacuum-packed Pork at Low Temperature

Abstract

Pathogenic Yersinia enterocolitica serotypes O:3, O:5,27, O:8 and O:9 were inoculated into sliced and ground pork, and the samples were stored under vacuum or aerobic conditions at 2 and degrees C. All serotypes survived for 5 weeks in pork with or without vacuum packing without any discernable increases in their population. In sterilized pork with or without vacuum packing, there was no evident growth of Y. enterocolitica. In pork broth in which the pH had been artificially adjusted to 6.8, the growth of Y. enterocolitica was faster than that at 5.7. It is suggested that the growth of Y. enterocolitica in pork with or without vacuum packing may be inhibited by pH but not by the microflora or lactic acid bacteria in pork.