This study isolated Bacillus cereus from soft soybean curds and developed a dynamic model to describe the kinetic behavior of B. cereus isolates during transfer and storage. B. cereus were first isolated from soft soybean curds. A mixture of B. cereus isolates was then inoculated in soft soybean curd and the bacterial cell counts were enumerated during storage at 10-30°C. The B. cereus cell counts were fitted to the Baranyi model to calculate growth rate ( µ max ; log CFU/g/h) and lag phase duration ( LPD ; h). These kinetic parameters were then analyzed with a polynomial equation to evaluate the effects of temperature on the kinetic parameters. The developed model was validated with observed values, and the differences between predicted and observed values were determined by calculating the root mean square error ( RMSE ). A dynamic model was then developed with a combination of primary and secondary models to describe B. cereus growth under changing temperature conditions B. cereus was detected in 2 soft soybean curd samples (5.1%) at 0.7 log CFU/g. The µ max ranged from -0.04 to 0.47 log CFU/g/h, and ln ( LPD ) ranged from 0.68 to 0.04 h, depending on storage temperatures. The model performance was appropriate with a 0.216 RMSE and accurately described the kinetic behavior of B. cereus in soft soybean curd samples. These results suggest that B. cereus can contaminate soft soybean curds and that the models developed with the B. cereus isolates are useful in describing the kinetic behavior of B. cereus in soft soybean curd.

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