不同变温处理对徐香猕猴桃后熟生理的影响

Effects of Different Variable Temperatures Treatments on Post-ripening Physiology of‘Xuxiang’Kiwi Fruit

为研究不同变温处理对徐香猕猴桃后熟生理的影响,探索变温催熟技术在猕猴桃上的应用,分别以在0℃冷库中贮藏0d(S1)和30d(S2)的徐香猕猴桃为试材,采取3种方式进行催熟处理,即处理1(5℃处理24h→10℃处理24h→15℃处理至可即食)、处理2(15℃处理24h→25℃处理24h→15℃处理至可即食)、处理3(15℃恒温处理至可即食),定期测定果实硬度、可溶性固形物含量、可滴定酸含量、呼吸强度、乙烯释放速率、VC含量等生理指标,至果实达即食状态,随后考察不同处理猕猴桃货架期间(常温和4℃)失重率和腐烂率的变化。结果表明,不同催熟处理组的徐香猕猴桃后熟期间品质差异较大。对S1组徐香猕猴桃进行变温催熟处理时,以处理2组的果实催熟时间最短,8d达到即食状态,分别较处理3和处理1提前2d和4d,且催熟期间处理2组的果实硬度、可滴定酸含量下降最快,可溶性固形物含量上升明显快于处理1和处理3,呼吸和乙烯峰值提前,但VC含量和货架期间果实失重率变化与其他处理组无显著差异;对S2组猕猴桃进行变温催熟处理时,各处理组催熟时间均较S1组缩短2d,同样以处理2组的催熟时间最短(6d)。

In this study,the effects of different variable temperatures treatments on the post-ripening physiology of‘Xuxiang’kiwi fruit were investigated and the application of variable temperatures ripening technology in kiwi fruit was explored.The‘Xuxiang’kiwi fruit stored in cold storage at 0℃for 0 d(S1)and 30 d(S2)were respectively used as test materials,and three methods were adopted to accelerate ripening,namely treatment 1(5℃for 24 h→10℃for 24 h→15℃to ready-to-eat),treatment 2(15℃for 24 h→25℃for 24 h→15℃to ready-to-eat),treatment 3(15℃to ready-to-eat at constant temperature),then the fruit hardness,soluble solid contents,titratable acid contents,respi⁃ratory intensity,ethylene release rates,VC contents and other physiological indicators were measured regularly until the fruits reached the ready-to-eat state.Subsequently,the changes of weight loss rates and decay rates during the shelf life(room temperature and 4℃)under different treatments of kiwi fruit were investigated.The results showed that the qualities of‘Xuxiang’kiwi fruit in different ripeness treatment groups were significantly different during the postripening period.When changing temperatures accelerating ripening treatment was applied to S1‘Xuxiang’kiwi fruit,the fruits of treatment 2 had the shortest ripening time and reached the ready-to-eat state at 8 d,which was 2 d and 4 d earlier than that of treatment 3 and treatment 1,respectively.Besides,during the ripening period,the fruits hardness and titrable acid contents of treatment 2 had the fastest decline,while soluble solid contents increased significantly faster than that of treatment 1 and treatment 3.The peaks of respiration and ethylene of treatment 2 were advanced,but the changes of VC contents and fruits weight loss rates during shelf life were not significantly different from those in other treatment groups.While when changing temperatures accelerating ripening treatment was applied to S2‘Xux⁃iang’kiwi fruit,the ripening time of kiwi fruit in group S2 was all 2 d shorter than that in group S1,and the ripening time in treatment 2 was also the shortest(6 d).