Modelling and predicting the effect of temperature, water activity and pH on growth of Streptococcus iniae in Tilapia.
OBJECTIVE
To evaluate and model the growth of Streptococcus iniae affect by temperatures (10-45 degrees C), water activity (A(w); 0.995-0.957), and pH (5-8).


RESULTS
Temperatures, A(w), and pH were adjusted. The behaviour of S. iniae was studied and modelled. Growth curves were fitted by using logistic, Gompertz, and Baranyi models. The maximum growth rates obtained from the primary model were then modelled as a function of temperature, A(w), and pH using the Belehradek-type models for secondary model. The optimum values for growth were found to be in the range of 35-40 degrees C, A(w) 0.995-1, and pH 6-7. The statistical characteristics of the models were validated by r(2), mean square error, bias, and accuracy factors. The results of validation indicated that Baranyi model performed the best.


CONCLUSIONS
The effect of temperature, A(w)/NaCl, pH control of S. iniae in tilapia could be satisfactorily predicted under current experimental conditions, and the proposed models could serve as a tool for this purpose.


CONCLUSIONS
The suggested predictive model can be used for risk assessment concerning S. iniae in tilapia.
Zhou
K
K
College of Food Science & Nutritional Engineering, East District, China Agricultural University, Beijing, China.
Cui
T T
TT
Li
P L
PL
Liang
N J
NJ
Liu
S C
SC
Ma
C W
CW
Peng
Z H
ZH
D000818:Animals; D015169:Colony Count, Microbial; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D008433:Mathematics; D008954:Models, Biological; D013291:Streptococcus / Q000254:growth & development*; D013696:Temperature; D017210:Tilapia / Q000382:microbiology*; D014867:Water
D014867:Water