壳聚糖-蒙脱土复合涂膜在常温下对荔枝货架期及品质的影响

Effect of Chitosan-montmorillonite Coating on Shelf Life and Quality of Litchi Fruit Under Ambient Temperature

在室温下评估了壳聚糖和壳聚糖-蒙脱土(MMT)涂膜对荔枝存放8天的失重率、硬度、可溶性固形物、维生素C、可滴定酸含量、果皮褐变、多酚氧化酶活性和过氧化物酶活性的影响。未进行涂膜处理的荔枝作为对照组。壳聚糖和壳聚糖-蒙脱土涂膜处理的荔枝失重率显著低于对照组。与壳聚糖涂膜和对照组的荔枝相比,壳聚糖-蒙脱土涂膜能有效保持荔枝的硬度,并能延缓可溶性固形物、维生素C、可滴定酸含量和果皮褐变指数PPO、POD等有害变化。壳聚糖-蒙脱土涂膜可有效抑制荔枝的多酚氧化酶和过氧化物酶活性。结果表明,壳聚糖-蒙脱土涂膜可延缓荔枝的老化过程,有效延长其货架期。

The weight loss,hardness,soluble solid content,vitamin C,titrated acid,pericarp browning,polyphenol oxidase,and peroxidase activity of litchi coated with chitosan and chitosan-montmorillonite(MMT)for 8 days at room temperature was tested.Litchi stored without coating was used as control group.The weight loss of litchi coated with chitosan and chitosan-MMT coating was significantly lower than that of control group.The chitosan-MMT coating would effectively maintain the hardness of litchi and could retard the harmful changes in soluble solid content,vitamin C,titrated acid,and pericarp browning index when compared to chitosan coating and control group.The chitosan-MMT coating could effectively suppress the polyphenol oxidase and peroxidase activity of litchi.The results showed that the chitosan-MMT coating could be used to delay the aging process of litchi and extend its postharvest life.