Abstract: In this paper, the growth of S. aureus in raw milk at 15, 25 ℃ and 37 ℃ in winter, spring and summer was studied. The Logistic and Gompertz models were used to establish a model predict describing the growth of S. aureus in raw milk. The root mean square errors (RMSE) of the Gompertz model in winter, spring and summer were 0.0936, 0.1057 and 0.1032, respectively. The RMSE values of the Logistic model were 0.1498, 0.1926 and 0.1857 in three seasons. These results indicated that the Gompertz model can predict the growth rate of S. aureus more accurately than the Logistic model. Meanwhile, a square root model has been developed predicting the growth rate of S. aureus in raw milk as a function of temperature.

Key words: raw milk, Staphylococcus aureus, mathematical model