Mathematical modeling of microbial growth in fresh filled pasta stored at different temperatures

Growth curves for a selection of pertinent microorganisms in ricotta and ri cotta-filled ravioli were analyzed in terms of Gompertz's model, The growth of Enterobacteriaceae, molds and yeasts and psychrotrophic microorganisms during storage at 0, 4, 8 and 10C was determined. Lag phase duration and sp ecific growth rate were inversely related. The activation energies from an Arrhenius-type equation were calculated for the microorganisms under study. For ricotta samples, molds and yeasts were the most sensitive organisms sh owing E-mu values of 74.60 KJoule/mol while Enterobacteriaceae and psychrot rophic microorganisms had E-mu values of 24.30 and 25.70 KJoule/mol, respec tively. For ricotta-filled ravioli samples, the three microorganisms showed activation energies in the range of 31.47-32.99 KJoule/mol; hence the temp erature dependence of their growth rates was comparable. Results allow to p redict microbial growth of different microorganisms in ricotta and ricotta- filled ravioli when exposed to different storage temperatures.