AN EMPIRICAL EQUATION FOR THE DESCRIPTION OF OPTIMUM VARIABLE RETORT TEMPERATURE PROFILES THAT MAXIMIZE SURFACE QUALITY RETENTION IN THERMALLY PROCESSED FOODS

Abstract

It has been previously shown that, when compared with the traditional constant retort temperature profiles, variable retort temperature profiles allow a modest increase in quality retention during the sterilization of packed foods. When the minimization of the process time with a constraint on the minimum surface quality is considered, variable retort policies show significant reductions on process times when compared to equivalent optimum constant retort temperature profiles. However the results were presented on a case by case basis and no effort was done to try to generalize this principle. In order to allow the generalization of the use of variable profiles we present in this article an empirical formula, developed based on the analysis of calculated optimum variable retort temperature profiles, that allows an accurate description of optimum variable temperature profiles. The use of the proposed equation allows a substantial reduction on the calculation effort necessary for the calculation of optimum variable retort temperature profiles.