Growth and predictive model of Bacillus cereus on blanched spinach with or without seasoning at various temperatures

Abstract

The growth of Bacillus cereus on blanched spinach with or without seasoning at various temperatures (15, 20, 25, 30, and 35A degrees C) was investigated. The number of B. cereus on blanched spinach stored at 35A degrees C was significantly increased and resulted in maximum populations (7.8 log CFU/g) after 10 h. However, the growth rate of B. cereus on blanched spinach with seasoning stored at 35oC was lower than on blanched spinach without seasoning. The growth rate (GR) of B. cereus on blanched spinach stored at 15A degrees C was lower than the other temperatures. The lag time (LT) of B. cereus on blanched spinach with seasoning was longer than blanched spinach without seasoning. Primary growth models of B. cereus on blanched spinach fit well to a modified Gompertz model (blanched spinach R-2 =0.98; blanched spinach with seasoning R-2 =0.96). These results might be used for developing safe storage guidelines for cooked vegetable at various temperatures.