This study developed predictive models for the kinetic behavior of Staphylococcus aureus on pro- cessed cheeses. Mozzarella slice cheese and cheddar slice cheese were inoculated with 0.1 ml of a S. aureus strain mixture (ATCC13565, ATCC14458, ATCC23235, ATCC27664, and NCCP10826). The inoculated samples were then stored at 4 o C (1440 h), 15 o C (288 h), 25 o C (72 h), and 30 o C (48 h), and the growth of all bacteria and of S. aureus were enumerated on tryptic soy agar and mannitol salt agar,

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... spectively. The Baranyi model was fitted to the growth data of S. aureus to calculate growth rate (µ max ; log CFU·g −1 ·h −1 ), lag phase duration (LPD; h), lower asymptote (log CFU/ g), and upper asymptote (log CFU/g). The growth parameters were further analyzed using the square root model as a function of temperature. The model performance was validated with observed data, and the root mean square error (RMSE) was calculated. At 4 o C, S. aureus cell growth was not observed on either processed cheese, but S. aureus growth on the mozzarella and cheddar cheeses was observed at 15 o C, 25 o C, and 30 o C. The µ max values increased, but LPD values decreased as storage temperature increased. In addition, the developed models showed acceptable performance (RMSE = 0.3500-0.5344). This result indicates that the developed kinetic model should be useful in describing the growth pattern of S. aureus in processed cheeses.