壳聚糖涂膜对机械伤苹果抗性生理特征的影响

Effects of Chitosan Coating on Resistance Physiology of Mechanical Injury Apple Fruit

为了提高苹果采后抗机械损伤能力,减少贮藏损失,以红富士苹果为材料,通过人工模拟机械伤试验,研究壳聚糖涂膜对损伤红富士苹果常温贮藏条件下果肉褐变、相关酶活性及抗性相关物质的影响,探索壳聚糖涂膜在果蔬防腐保鲜上的应用。结果显示:壳聚糖涂膜处理科显著减少红富士苹果果实机械伤口的扩张,提高机械伤果实的总酚含量,降低PPO活性,从而有效抑制机械伤苹果贮藏期间的果肉褐变的发生。同时,壳聚糖涂膜处理可提高机械伤苹果的POD和PAL活性,延缓酚类物质含量的下降,促进体内木质素的合成。研究表明,壳聚糖涂膜处理能够有效防止机械伤苹果贮藏期间的酶促褐变,减少果肉组织中有害物质的积累,促进愈伤组织的形成,从而增强了机械伤苹果的抗性,有效延缓了果实衰老。

In order to improve the apple postharvest resistance to mechanical damage to reduce storage los- ses,to explore the application of chitosan coating on fruit and vegetable preservation. With Fuji apple as material, by artificial simulation mechanical injury trials, we researched the flesh browning, related enzyme activities and resistance substances of Fuji apple at room temperature storage conditions. The results showed that： the chitosan coating reduces mechanical wound expansion, increases mechanical injury total phenol content of fruit,decreases PPO activity, so as to effectively inhibit the browning of the mechanical injury apple flesh during storage. The chitosan coating increases the mechanical injury apple POD and PAL activities,slows the decline of the phenolic substances, promotes the synthesis of lignin. Chitosan coating can effectively prevent enzymatic browning of mechanical injury apple during storage,reduce the accumula- tion of harmful substances in the putp tissue,and promote the formation of callus. Thus the chitosan coat- ing can increase the resistance to mechanical injury apple, effectively delay senescence.