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

It has been previously shown that, when compared with the traditional constant retort temperature profiles, variable retort temperature prof iles allow a modest increase in quality retention during the steriliza tion of packed foods. When the minimization of the process time with a constraint on the minimum surface quality is considered, variable ret ort policies show significant reductions on process times when compare d to equivalent optimum constant retort temperature profiles. However the results were presented on a case by case basis and no effort was d one to try to generalize this principle. In order to allow the general ization of the use of variable profiles we present in this article an empirical formula, developed based on the analysis of calculated optim um variable retort temperature profiles, that allows an accurate descr iption of optimum variable temperature profiles. The use of the propos ed equation allows a substantial reduction on the calculation effort n ecessary for the calculation of optimum variable retort temperature pr ofiles.