Inactivation kinetics of Bacillus atrophaeus in liquid hydrogen peroxide for aseptic package sterilization
Manoj Sawale, Xiang Cheng, Rishi Drolia, Patnarin Benyathiar, Ferhan Ozadali, Arun K. Bhunia, Dharmendra K. Mishra
Abstract
Liquid hydrogen peroxide is used as a common sterilant for the aseptic packaging materials. Based on the Food Safety Objective (FSO) for specific products, a surrogate organism, Bacillus atrophaeus, is used to validate the sterilization processes. This study aims to develop a methodology for the kinetic inactivation parameter estimation of B. atrophaeus. Spores of B. atrophaeus were challenged with various peroxide concentrations (20%, 28%, and 33%; v/v) and temperatures such as 23, 55, 71.1, and 82.2 °C. The log-linear and Weibull models were used for the inactivation models for liquid peroxide at different temperatures. The parameters were estimated at a reference temperature of 80 °C for log-linear and Weibull models. With peroxide concentrations of 20, 28, and 33%, the log-linear model estimated D values were 0.95, 0.47, and 0.08 min and z values were 94.67, 86.86, and 41 °C, respectively. The Weibull model δ values were 0.31, 0.23, and 0.05 min with a z value of 85.18, 81.23, and 41.39 °C for 20, 28, and 33% peroxide, respectively. The RMSE values varied from 0.60 to 0.79 log CFU/ml, the sum of the squares was between 27.3 and 39.7, and the parameters' relative errors were less than 6%.