Mathematical modelation of the growth of lactobacillus casei

Abstract

The adjustment of mathematical equations to predict the growth of Lactobacillus casei in different conditions of temperature was the objective of the present work. Data from their growth at different temperatures with the Gompertz modified and sigmoidal logistical equations were adjusted. The statistical indexes used to evaluate the quality of adjustment to the model were the multiple determination coefficient (R²) and F test. The T-Test test was used to compare the estimate and experimental values of initial counts (A), the cycles of logarithmic growth (C) and maximum growth (Nmax). The Gompertz modified equation adjusted for the three studied temperatures, while the logistical sigmoidal function did not adjust at 28 ± 2 ºC. The Gompertz equation was not effective to predict with accuracy the kinetic parameters of the growth of casei, while the sigmoidal was effective. The logistical sigmoidal function was the best model to predict the growth of casei at temperatures lower than 28 ºC.