Establishment of growth predictive model of Vibrio parahaemolyticus in bread shrimp under different pH condition

To study the impact of pH to the growth law of Vibrio parahaemolyticus in the process of bread shimp, growth curves under different pH (5.5, 6.0, 6.5, 7.0, 7.5, 8.0 and 8.5, respectively) were determined. The modified Compertz, modified Logistic and Baranyi models, respectively, were applied to fit the growth curves by Origin 8.0 software and DMFit software, the maximum specific growth rates was calculated by the primary model with the highest coefficient of determination. The modified Arrhenius model was used to fit the curves between the maximum specific growth rates and pH for the establishment of the secongary model. Results showed that the modified Compertz model (R2=0.99) was more accurate and useful in fitting V. parahaemolyticus growth curves than the modified Logistic and Baranyi & Robert models, respectively. And the secondary model had a high goodness-of-fit (R2=0.98) . The values of bias factor and accuracy factor were also acceptable statistically that were close to 1.0. The predictive models were highly reliable. These could effectively predict the growth of Vibrio parahaemolyticus under above pH condition.