College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Food Microbiol. 2010 Feb;27(1):94-100. doi: 10.1016/j.fm.2009.09.012. Epub 2009 Oct 2.
The inactivation of Salmonella typhimurium inoculated into acidified carrot juice subjected to dense phase carbon dioxide (DPCD) was investigated. The pressures in the study were 10, 20 and 30 MPa, the temperatures were 32, 37 and 42 degrees C, and the treatment time was 5-90 min. The inactivation effect of DPCD was enhanced by increasing pressure and temperature. The sigmoid inactivation curves were characterized with the lag phase, exponential inactivation phase, and resistant phase. The inactivation curves were fitted to the modified Gompertz equation and the modified Logistic equation, the modified Gompertz equation was superior since its lowest residual sum of squares (RSS) was lower although there was no significant difference of goodness-of-fit between both models as indicated by F-test. The lambda (the duration of the lag phase) and t(4-D) (the time necessary to achieve 4-log cycles reduction) decreased with increasing pressure or temperature. The k(dm) (the maximum specific value of the inactivation rate, min(-1)) increased with increasing temperatures, and decreased with increasing pressures. The activation energy (Ea) and the activation volume (Va) necessary for inactivating S. typhimurium by DPCD were 19.06-29.39 kJ mol(-1) and 18.89-58.27 cm(3) mol(-1).
研究了高密度二氧化碳（DPCD）处理酸化胡萝卜汁中接种的鼠伤寒沙门氏菌的失活动力学。研究中的压力分别为 10、20 和 30 MPa，温度分别为 32、37 和 42°C，处理时间为 5-90 min。通过增加压力和温度，增强了 DPCD 的灭活效果。失活动力学曲线的特征为滞后期、指数灭活期和抗性期。使用修正的 Gompertz 方程和修正的 Logistic 方程对失活动力学曲线进行拟合，修正的 Gompertz 方程更优，因为尽管 F 检验表明两种模型的拟合优度没有显著差异，但它的最小残差平方和（RSS）较低。lambda（滞后期的持续时间）和 t（4-D）（达到 4 对数减少所需的时间）随压力或温度的升高而降低。k（dm）（最大特定灭活率，min（-1））随温度升高而增加，随压力升高而降低。DPCD 灭活 S. typhimurium 所需的活化能（Ea）和活化体积（Va）分别为 19.06-29.39 kJ mol（-1）和 18.89-58.27 cm（3）mol（-1）。
