High Pressure Inactivation and Survival of Pressure-Resistant Escherichia coli Mutants in Milk

摘要

Liquid milk is usually pasteurized or sterilized by heat treatment before it is consumed or used for other applications. Recently, high pressure has been proposed as an alternative to thermal treatment that allows an increase in the shelf-life of milk, while maintaining most of its raw qualities. Information on the response of microorganisms to pressure is necessary to further evaluate and optimize the process. In this respect, the development of high levels of pressure resistance in some strains of E. coli causes serious concern about the safety and stability of pressure-processed foods. In the current work, we studied the inactivation of these E. coli strains in milk by high pressure treatment alone, and in combination with lysozyme and/or nisin.