气调贮藏对‘红阳’猕猴桃果胶含量及相关酶活的影响

Effects of controlled atmosphere on the pectin content and relevant metabolizing enzyme activities of Hongyang kiwifruit

摘要研究了气调对采后‘红阳’猕猴桃贮藏期间果实硬度、果胶（可溶性果胶、原果胶）含量及果胶代谢相关酶（果胶甲酯酶PE、多聚半乳糖醛酸酶PG和纤维素酶CX）活性的影响。在温度（1-t-O．5）℃、相对湿度80％～98％的条件下，以空气为对照（CK），采用了4种不同的气调组分CA．（2％0：＋3％CO：）、CA：（2％O2＋6％CO：）、CA，（5％0：＋3％CO：）、CA。（5％O2＋6％CO2）。试验表明：红阳猕猴桃后期贮藏过程中，果实软化与PG和CX有密切联系，而与PE可能无直接联系。气调贮藏可显著延长果实贮藏期，其中CA．和CA，处理的果实贮藏期长达120d，而CA，可更有效地延缓果实硬度的下降，抑制细胞壁降解酶的活性，更好地保持‘红阳’猕猴桃的商品性。

In the present study, we evaluated the effects of controlled atmosphere on the content of pectin and the activities of relevant metabolizing enzymes （PE, PG, CX） in the kiwifruit euhivar Hongyang. Postharvest kiwifruits were stored under air （control） and air- 02 -CO2 atmosphere （1 ＋0.5~C , 80% -98% relative humidity） with dif- ferent gas compositions, i. e., CA1（2%02 ＋3%C02）, CA2（2%02 ＋6%C02）, CA3（5%02 ＋3%C02）, and CA4 （5% 02 ＋ 6% C02）. Results showed that the fruit soften was closely related with PG and CX, maybe had no direct re- lation with PE. Controlled atmosphere CAt and CA3 could significantly prolong postharvest storage period as long as 120 d. However, the controlled atmosphere CA~ was the most effective in suppressing the activities of cell wall-de- grading enzymes and preventing pectin decomposition, further delaying the fruit softening and extending the shelf life of Hongyang kiwifruits.