Predictive microbiology was utilized to model Staphylococcus aureus (S. aureus) growth and staphylococcal enterotoxin A (SEA) production in milk in this study. The modifed logistic model, modifed Gompertz model an...Predictive microbiology was utilized to model Staphylococcus aureus (S. aureus) growth and staphylococcal enterotoxin A (SEA) production in milk in this study. The modifed logistic model, modifed Gompertz model and Baranyi model were applied to model growth data of S. aureus between 15℃ and 37℃. Model comparisons indicated that Baranyi model described the growth data more accurately than two others with a mean square error of 0.0129. Growth rates generated from Baranyi model matched the observed ones with a bias factor of 0.999 and an accuracy factor of 1.01, and ft a square root model with respect to temperature; other two modifed models both overestimated the observed ones. SEA amount began to be detected when the cell number reached106.4 cfu ? mL-1, and showed the linear correlation with time. Besides, the rate of SEA production ftted an exponential relationship as a function of temperature. Predictions based on the study could be applied to indicate possible growth of S. aureus and prevent the occurrence of staphylococcal food poisoning.展开更多
基金Supported by"Academic Backbone"Project of Northeast Agricultural University(15XG26)the National High-level Talents Special Support Program of China
文摘Predictive microbiology was utilized to model Staphylococcus aureus (S. aureus) growth and staphylococcal enterotoxin A (SEA) production in milk in this study. The modifed logistic model, modifed Gompertz model and Baranyi model were applied to model growth data of S. aureus between 15℃ and 37℃. Model comparisons indicated that Baranyi model described the growth data more accurately than two others with a mean square error of 0.0129. Growth rates generated from Baranyi model matched the observed ones with a bias factor of 0.999 and an accuracy factor of 1.01, and ft a square root model with respect to temperature; other two modifed models both overestimated the observed ones. SEA amount began to be detected when the cell number reached106.4 cfu ? mL-1, and showed the linear correlation with time. Besides, the rate of SEA production ftted an exponential relationship as a function of temperature. Predictions based on the study could be applied to indicate possible growth of S. aureus and prevent the occurrence of staphylococcal food poisoning.