护色处理对冻藏香蕉片多酚氧化酶活性的影响

通过设计单一护色剂、不同浓度L-半胱氨酸、不同热处理时间及多因子护色处理四个实验研究其对冻藏香蕉片多酚氧化酶(PPO)活性的影响,结果表明,5种护色剂均能有效地抑制冻藏香蕉片PPO活性,但L-半胱氨酸对其抑制效果更佳;随着护色液中Cys浓度的增加,残余PPO活力呈下降趋势,表现为CK>0.05%Cys>0.1%Cys>0.2%Cys;热处理能有效地抑制冻藏香蕉片PPO活性,PPO活性随着热处理时间的增加而降低,但热处理却大大降低了冻藏香蕉片的品质;0.1%L-半胱氨酸、0.05%异抗坏血酸、0.1%蔗糖和0.1%氯化钙构成的护色剂组合能有效地抑制PPO活性,并起到良好的保质增脆效果。

Effect of color retention treatments on the polyphenol oxidase activity in freezing-stored banana slices

Four experiments included different single color-protecting solutions,different concentration of L-cysteine,different heat treatment time and multi-factor color retention treatments were designed to study the polyphenol oxidase(PPO) activity in freezing-stored banana slices.The results showed that five color-protecting solutions could inhibit the activity of PPO effectively in freezing-stored banana slices,and L-cysteine was best of them;the activity of PPO decreased with the concentration of L-cysteine increased,the order was:CK>0.05% Cys>0.1% Cys>0.2% Cys.Heat treatment could inhibit PPO activity effectively in freezing-stored banana slices,the activity of PPO decreased with the heat treatment time increased,but the heat treatment had greatly reduced the quality of the freezing-stored banana slices.The color-protecting solution compounded with 0.1% L-cysteine,0.05% erythorbic acid,0.1% sucrose and 0.1% calcium chloride could inhibit PPO activity effectively and play an important role in improving quality and increasing brittleness of banana slices.