Increased water activity reduces the thermal resistance of salmonella enterica in peanut butter

Abstract

Increased Water Activity Reduces the Thermal Resistance of Salmonella enterica in Peanut Butter Yingshu He, a Ye Li, a Joelle K. Salazar, a Jingyun Yang, b Mary Lou Tortorello, c Wei Zhanga Institute for Food Safety and Health, Illinois Institute of Technology, Bedford Park, Illinois, USAa; Methodology Center, Pennsylvania State University, University Park, ennsylvania, USAb; U.S. Food and Drug Administration, Bedford Park, Illinois, USAc Increased water activity in peanut butter significantly (P < 0.05) reduced the heat resistanceof desiccation-stressed Salmonella enterica serotypes treated at 90°C. The differencein thermal resistance was less notable when strains were treated at 126°C. Using scanning electron microscopy, we observed minor morphological changes of S. enterica cells r sulting from desiccation and rehydration processes in peanut oil. © 2013, American Society for Microbiology. All Rights Reserved.