研究了高压脉冲电场(pulsed electric fields,PEF)对接种于苹果清汁中的大肠杆菌(Escherichia coli)和金黄色葡萄球菌(Staphylocuccus aureus)的钝化效果。研究显示,随着电场强度、处理时间和样品电导率的增大,PEF对大肠杆菌和金黄色葡萄球菌的钝化效果增加,其中金黄色葡萄球菌对PEF更敏感。电场强度和处理时间均对大肠杆菌和金黄色葡萄球菌的残活率对数值lgS有极显著影响(P<0.01)。大肠杆菌和金黄色葡萄球菌的临界电场强度EC分别为15.9 kV/cm和16.4 kV/cm。双极性脉冲比单极性脉冲对大肠杆菌和金黄色葡萄球菌的钝化效果好(P<0.01)。输入能量密度越高,PEF对大肠杆菌和金黄色葡萄球菌的钝化效果越好。

The inactivation effect of pulsed electric fields(PEF) on E.coli and S.aureus inoculated into apple juice was investigated.As increasing the electric field strength,total treatment time and electrical conductivity,the inactivation effect of E.coli and S.aureus increased.S.aureus is more sensitive to PEF than E.coli.Both the electric field strength and the total treatment time have a significant inactivation effect on E.coli and S.aureus(P < 0.01).The critical electric field strengths of E.coli and S.aureus are 15.9 kV/cm and 16.4 kV/cm,respectively.Bipolar appears more efficient than monopolar(P < 0.01).The more the energy density input,the better the inactivation effect of PEF on E.coli and S.aureus.