二甲基二碳酸盐联合动态超高压对模拟果汁的杀菌效果研究

Inactivation of Microorganisms in Model Fruit Juice System by Dynamic Ultra-high Pressure Combined with Dimethyl Carbonate

摘要:

本文研究了二甲基二碳酸盐（DMDC）联合动态超高压对模拟果汁中三种挑战污染菌（大肠杆菌、酿酒酵母、肠膜状明串珠菌）的杀菌效果。结果表明：单独动态超高压对三种挑战污染菌的杀菌效果随着压力增大而显著增强（p<0.05），其中在相同处理压力下，对大肠杆菌的杀菌最好，但即使在100 MPa的压力处理下，大肠杆菌也仅下降1.2个对数；向含挑战污染菌的模拟果汁（25 ℃）中添加250 mg/L的DMDC 2 h后，大肠杆菌和酿酒酵母均被完全杀灭，而肠膜状明串珠菌对DMDC具有很强的耐受性，仅下降了1.7个对数，且继续延长DMDC的处理时间，其数量下降也不再明显；当DMDC（250 mg/L）与动态超高压联合处理时，它们对模拟果汁中的肠膜状明串珠菌的杀菌作用具有明显的协同增效效果（p<0.05）。另外，DMDC与动态超高压先后处理次序对肠膜状明串珠菌的杀菌效果也有影响。

Abstract:

Inactivation of dynamic ultra-high pressure (DUHP) combined with dimethyl carbonate (DMDC) on E. Coli, Saccharomyces cerevisiae and Leuconostoc mesenteroides in model juices were investigated. The results showed that the effect of DUHP on inactivation of three strains in model juices gradually increased as the pressure increased (p<0.05). UHP had the best sterilization effect on E. Coli under the same pressure. But even under the pressure of 100 MPa, the reduction of E. Coli was not more than 1.2 Lg cycles. After 250 mg/L DMDC was added to the model juices, E. Coli and Saccharomyces cerevisiae were completely inactivation after 2 h, while Leuconostoc mesenteroides only decreased 1.7 Lg cycles. No significant reduction was displayed as treatment time increased. DUHP combined with DMDC showed a significantly synergistic effect on the inactivation of Leuconostoc mesenteroides (p<0.05), and its sterilization effect was affected by the sequence of DMDC addition.