超高压与重组果胶甲酯酶抑制剂联合应用对鲜榨橙汁果胶甲酯酶活性及品质的影响

为了探究超高压与重组果胶甲酯酶抑制剂(recombinant pectin methylesterase inhibitor,rPMEI)联合处理对鲜榨橙汁中果胶甲酯酶(pectin methylesterase,PME)活性及品质的影响,研究了超高压(400、500和600 MPa,5 min,20 ℃)与重组果胶甲酯酶抑制剂对橙汁微生物、PME酶活、色泽和V_C含量的影响。结果表明:超高压处理条件为500 MPa/5 min,rPMEI添加浓度为0.06 mg/mL时,橙汁中的菌落总数、霉菌与酵母菌数均能达到农业行业标准《NY/T 434-2016绿色食品、果蔬汁饮料》所规定的要求,同时PME被完全钝化;橙汁色泽变化显著小于热处理组(ΔE^*=1.22<2.26);V_C保留率为85.1%,显著高于热处理组(保留率=8.33%)。

Effect of Ultra High Pressure Combined with Recombinant Pectin Methylesterase Inhibitor on Pectin Methylesterase Activity and Quality of Fresh Orange Juice

To investigate the effects of ultra-high pressure and recombinant pectin methylesterase inhibitor(rPMEI)on the activity and quality of pectin methylesterase(PME)in freshly squeezed orange juice,the effects of ultra-high pressure(400,500 and 600 MPa,5 min,20 ℃)and recombinant pectin methylesterase inhibitor on orange juice microorganisms,PME activity,color and VC content were studied. The results showed that when the ultra-high pressure treatment condition was 500 MPa/5 min and the rPMEI concentration was 0.06 mg/mL,the total number of colonies,mold and yeast in the orange juice could reach the agricultural industry standard NY/T 434-2016 Green Food-Fruit and Vegetable Drinks,PME was completely passivated;the color change of orange juice was significantly lower than that of the heat treatment group(ΔE^*=1.22<2.26);the VC retention rate was 85.1%,which was significantly higher than the heat treatment group(retention rate=8.33%).