不同薄膜包装对桑葚采后品质的影响

为探讨不同薄膜包装对桑葚采后品质的影响，以‘滇缅1号’桑葚为材料，在（5±1）℃、相对湿度80%～90%贮藏条件下，研究5 种不同厚度薄膜（15.55 μm的带孔聚乙烯袋（CK）、5.4 μm聚乙烯袋（P1）、12.75 μm的聚乙烯袋（P2）、15.55 μm的聚乙烯袋（P3）、32.7 μm的聚乙烯袋（P4））对桑葚贮藏效果的影响。结果表明，与对照相比，薄膜包装处理均可降低采后桑葚的腐烂指数，其中P4处理的效果最理想。此外，P4处理可显著延缓采后桑葚果实糖酸比的增加，并维持较高的总酚含量及抗氧化活性。通过对不同包装袋内气体比例的分析发现，较其他薄膜包装处理相比，P4薄膜包装可在包装袋微环境中形成高体积分数CO2（5.9%～6.9%）和低体积分数O2（6.2%～8.5%）。可见，P4薄膜包装即32.7 μm的聚乙烯袋包装对采后桑葚品质的调控与其形成的高体积分数CO2和低体积分数O2有关。

Effects of Different Packaging Films on Postharvest Quality of Mulberry

This study aimed to investigate the influence of packaging films with different thicknesses on postharvest quality
of mulberry. In this experiment, mulberries (Morus indica L., the Dianmian 1 cultivar) were treated respectively with five
packaging films, i.e., 5.4 μm polyethylene bag (P1), 12.75 μm polyethylene bag (P2), 15.55 μm polyethylene bag (P3),
32.7 μm polyethylene bag (P4), and 15.55 μm polyethylene bag with four holes (CK) and then stored at (5 ± 1) ℃ and 80%–
90% relative humidity. The results showed that all the experimental groups could decrease fruit decay indexes in comparison
to the CK, of which P4 treatment had the most significant effect. Besides, P4 treatment could significantly delay the increase
in sugar/acid ratio and maintain higher levels of phenols content and antioxidant activity in mulberries. The gas composition
in packages showed that P4 treatment could maintain higher concentration of CO2 (5.9%–6.9%) and lower concentration of
O2 (6.2%–8.5%) when compared with other treatments. It is thus clear that the effect of P4 treatment on mulberry quality has
an association with its higher CO2 concentration and lower O2 concentration.