Abstract:This essay studied the changes of lignification and related enzymes activities during refrigeration in order to extend shelf life of loquat.In this experiment，chitosan and whey protein were used as the main filmforming substrates，and Litsea cubeba essential oil of different concentrations （0 %，3 %，6 %，9 %）were added to make the compound membrane liquid，the loquat was coated with the liquid and refrigerated at 8 ℃.The results showed that，compared with the control group ，the composite membrane solution with 6%of Litsea cubeba oil could effectively reduce weight loss rate，increase juice yield and reduce the accumulation of malondialdehyde.On the 25th day of retrigeration，comparing with the control group，the weight loss rate of coating treatment group reduced by 48.62%，the juice yield rate increased by 15.35%，and the malondialdehyde content was reduced by 29.62 %.In addition，the compound membrane solution could significantly inhibit the activity of polyphenol oxidase （PPO），peroxidase （POD）and phenylalaninammo-nialyase（PAL）.The lignin content of coating treatment group was reduced by 24.50 % on the 25th day of refrigeration so as to achieve the purpose of maintaining the preservation quality and extending the shelf life of loquat.