1-MCP处理结合激光微孔膜包装对采后水蜜桃的保鲜效果

以“霞辉8号”水蜜桃为试材，采用2 μL/L 1-甲基环丙烯(1-Methylcyclopropene, 1-MCP)熏蒸处理果实24 h后用激光微孔膜包装，研究1-MCP处理结合激光微孔膜(1-MCP+LMF)包装对水蜜桃保鲜效果的影响。结果表明，1-MCP+LMF包装处理显著降低了水蜜桃冷藏期间的呼吸强度和失重率（P<0.05），贮藏35 d时分别比对照组低18.84 mg CO₂/kg·h和17.87%；可溶性固形物含量从贮藏时的7.92%上升到8.38%，对照组上升到10.04%；抗坏血酸含量贮藏结束时为对照组的3.39倍；超氧化物歧化酶、过氧化氢酶和抗坏血酸氧化酶活力显著高于对照（P<0.05），从而减少了H₂O₂的积累，贮藏35 d后H₂O₂含量为对照组的78.86%；同时，1-MCP+LMF包装还抑制了多聚半乳糖醛酸酶和β-葡萄糖苷酶活力，进而延缓了原果胶含量的下降和可溶性果胶含量的上升，维持了桃果实较高的硬度，贮藏结束时硬度为贮藏时的42.88%，而对照组下降24.56%。以上结果表明，1-MCP处理结合激光微孔膜包装可显著减少水蜜桃冷藏期间失重和腐烂，延缓水蜜桃营养品质下降，抑制生理生化代谢活动，其货架寿命在5 ℃条件下可延长至28 d。

Effect of 1-MCP Treatment Combined with Laser Microporous Film Packing on the Preservation Effect of Honey Peach Fruit

In this study, “Xiahui 8” honey peach fruit was used as a test material to investigate the synergistic preservation effect of 1-methylcyclopropene (1-MCP) and laser microporous film (LMF). The peach fruits were fumigated with 2 μL/L 1-MCP for 24 h, then packed in LMF. The results showed that 1-MCP+LMF significantly reduced the respiratory intensity and weight loss of peach during cold storage (P<0.05), which were 18.84 mg CO₂/kg·h and 17.87% lower than the control at 35 d, respectively. Soluble solid content increased from 7.92% at the beginning of storage to 8.38% at the end of storage time, while it increased to 10.04% in the control; ascorbic acid content was 3.39 times higher than that of control at the end of storage. Superoxide dismutase, catalase and ascorbate oxidase activities were significantly higher than the control (P<0.05), thus reducing the accumulation of H₂O₂, with the H₂O₂ contents being 78.86% of the control after 35 d of storage. At the same time, 1-MCP+LMF also inhibited polygalacturonase and β-glucosidase activities, which in turn delayed the decrease in protopectin content and the increase in soluble pectin content, maintaining the high hardness of peach fruit. The hardness at the end of storage was 42.88% of the initial hardness, compared to 24.56% in the control. These results indicate that 1-MCP treatment combined with laser microporous film packaging can significantly reduce the weight loss and decay rate, delay the decline of nutritional quality, and inhibit physiological and biochemical metabolic activities of peach during cold storage, and thereby extending its shelf-life up to 28 days at 5 ℃.