不同O_(2)和CO_(2)浓度梯度对酥梨采后生理及果实褐变的影响

Effects of Different O_(2) and CO_(2) Concentration on Postharvest Physiology and Fruit Browning of‘Suli’Pears

以酥梨为试材,研究了(0±0.5)℃条件下不同O_(2)浓度梯度和CO_(2)浓度梯度的气调贮藏对酥梨采后生理及果实褐变的影响。结果表明:在贮藏期内,当CO_(2)浓度为0%时,随着O_(2)浓度的降低,在一定程度上可以延缓酥梨果肉组织相对电导率的升高、酚类物质的下降、多酚氧化酶活性的上升及色泽的转黄;但当O_(2)浓度为1.5%时,会对酥梨果实造成伤害,引起多酚氧化酶活性上升,果心褐变指数升高;当O_(2)浓度为5%时,CO_(2)浓度的升高有效保持了果实的硬度、色泽;但当CO_(2)浓度为8%时,会导致酥梨果实相对电导率增幅加大,果心、果肉酚类物质氧化加剧,果心褐变指数升高。综上所述,酥梨适宜的气调指标阈值为CO_(2)<2%,O_(2)为3%~5%。

The effects of controlled atmosphere storage with different O_(2) and CO_(2) concentration on postharvest physiology and fruit browning of‘Suli’pears stored at(0±0.5)℃were studied.The results showed that when the CO_(2) concentration was 0%,the decrease of O_(2) concentration could delay the increase of relative electrical conductivity of‘Suli’pear pulp tissue and PPO activity,the decrease of phenols,and the yellowing of fruit color,however 1.5%O_(2) concentration could cause the fruit damage,the increase of PPO activity and core browning index.When O_(2) concentration was 5%,the increase of CO_(2) concentration could effectively maintain fruit hardness and color,however 8%CO_(2) concentration could cause the significant increase of fruit relative electrical conductivity,aggravated oxidation of phenolic substances in fruit core and pulp,the increase of browning index of fruit core.In conclusion,the appropriate threshold value of controlled atmosphere index for‘Suli’pears storage was:CO_(2)<2%,O_(2)3%~5%.