To calculate the sterilizing value U, and hence, the microbial lethality F in thermal processes of the canned food, starting from the knowledge of heating time B, a mathematical modeling was carried out. Therefore it\u2019s useful to verify the desired microbial destruction (check problem) and it was obtained by reversing the mathematical approach carried out in a previous work [23] for the design problem, namely to calculate the retort heating time B, starting from a desired lethality F and, hence from the fh/U parameter. A comparison between the predicted fh/U, related to the lethality F calculated with the mathematical model of the present work and the desired Stumbo\u2019s values of fh/U, provided the following statistical indices: a mean relative error MRE=1.18\ub12.11%, a mean absolute error MAE=1.61\ub111.7 and a determination coefficient R2=0.991, better than ANN models. The mathematical procedure, quickly usable also with a spreadsheet, replaces the 57 Stumbo\u2019s tables and 18512 data sets in the Ball formula method
