不同降温方式下薄膜包装和保鲜剂对鸭梨贮藏品质和褐变的影响

Effects of film packaging and preservative on Pyrus bretschneideri storage qualities and fruit browning under different cooling methods

目的 研究降温方式、薄膜包装以及保鲜剂处理下鸭梨长期冷藏后品质的变化,尤其是对果实褐变的影响。方法 鸭梨果实分为4个处理:A(MAP)自发气调包装(modified atmosphere package,MAP)、B(MAP+EA)包装内放置乙烯吸收剂(ethylene absorbent, EA)、C (MAP+SF)包装内放置聪明鲜(smart fresh, SF)、D(CK)不包装直接装箱。每个处理的鸭梨一部分入0℃库直接冷藏,另一部分经缓慢降温至0℃,测定果实出库(210 d)以及货架(210 d+7 d)品质。结果 缓慢降温以及保鲜剂可有效维持鸭梨冷藏和货架品质,保持果面色泽,抑制果实衰老褐变。贮藏210 d时,缓慢降温+MAP+SF处理的鸭梨黑皮指数为0.038、果肉褐变率为0、果心褐变指数为0.111,优于直接冷藏下对照果实的0.143、22.62%和0.242。贮藏210d+7d时,缓慢降温+MAP+SF处理的鸭梨黑皮指数为0.101、果肉褐变率为0、果心褐变指数为0.142,优于直接冷藏下对照果实的0.304、17.36%和0.526果肉褐变率极显著低于直接冷藏+MAP+SF处理的果实(P<0.01)。结论 鸭梨果实经保鲜膜包装,包装内放置SF后经缓慢降温入库贮藏,可减少长期冷藏后果皮、果肉和果心褐变的发生。

Objective To study the quality of Pyrus bretschneideri under cooling method, film packaging and preservative treatment during long-term cold storage, especially the effects on fruit browning. Methods Four treatments were conducted, A(MAP) fruits were packed with ethylene film(modified atmosphere package, MAP), B(MAP+EA) ethylene absorbent(EA) and C(MAP+SF) smart fresh(SF) respectively were put in the package, D(CK)Pyrus bretschneideri were boxed without package as the control. Every treatment was divided to two parts, one part was put into 0 ℃ storage, while the other part was cooled slowly to 0 ℃. After 210 days of cold storage and 7 days shelf-life at 20 ℃, the quality of Pyrus bretschneideri was analyzed. Results Slow cooling method and preservative could effectively maintain fruit quality, preserve peel color and repress fruit browning during storage. After 210 days of storage, the peel browning index, flesh browning rate and core browning index of Pyrus bretschneideri treated with slow cooling method+MAP+SF were 0.038, 0 and 0.111 respectively, which were lower than 0.143, 22.62% and 0.242 of the control fruit under direct cooling. After 7 days of shelf-life, the peel browning index, flesh browning rate and core browning index of Pyrus bretschneideri treated with slow cooling method+MAP+SF were 0.101, 0 and 0.142, which were lower than 0.304, 17.36% and 0.526 of the control fruits treated by direct cooling, and flesh browning rate was significantly lower than of the fruit treated with direct cooling method+MAP+SF(P<0.01).Conclusion Pyrus bretschneideri is treated with package film and SF, then slowly cooled and stored in the warehouse, which can reduce the browning of skin, flesh and core after long-term cold storage.