Abstract
The acquired thermal inactivation data in the model solutions were used to develop a mathematical model for thermal inactivation of the bacterium Enterococcus faecium. The model is valid within the water activity range 0.97 to 0.99; pH = 6.0 to 7.6; temperature range 60 °C to 65 °C, and was determined in the microorganism concentration ranges of 10^2 per ml to 10^8 per ml of the model inactivation solution.
A predictive procedure in the Visual Basic language was developed for the spreadsheet MS Excel, which enables us calculation of the final concentration of the microorganism from input data for pH, aw, log No, temperature and duration of treatment. The proposed model was verified in experiments using cow and human milk.
In case of cow milk, the correspondence between the experimental and predicted data is highly satisfactory. In the case of human milk, the model predicts lesser effect of heating than manifested experimentally.