Research On Related Issues Of The Shelf Life Of'Hayward' Kiwifruit

Kiwifruit reachs the edible state after harvesting,through the post-ripening process After reaching the edible state,it is quickly decayed and deteriorated,and the commercial value of kiwifruit is greatly affected.Studies have shown that the nutritional value and antioxidant activity of domestic kiwifruit is better than thatin New Zealand,but the market price of domestic kiwifruit is much lower than that of kiwifruit in New Zealand.The post-maturing period of domestic kiwifruit is too long,but the storage period is short after ripening,which is seriously affecting the image of high-end fruit kiwifruit in consumers.Kiwifruits of New Zealand can be eaten when they are bought and can be stored when they are eaten.Consumers prefer to buy kiwifruit of New Zealand at a high price and do not want to consume domestic kiwifruit,which seriously affects the sustainable development of domestic kiwifruit.Actinidia deliciosa 'Hayward' is a newly late-maturing variety in New Zealand and is currently the main cultivar in the world.Therefore,this study uses 'Hayward' as raw material systematically to study the impact of harvest period on its shelf life,1-methylcyclopropene(1-MCP)on shelf life,shelf life prediction model,edible shelf life regulation,in order to lay a foundation for improving the image of domestic kiwifruit in consumers.It provides technical support for China's kiwifruit industry to catch up with and surpass the kiwifruit industry of New Zealand.The main results and conclusions in currentstudy are as follows:(1)Kiwifruit,which was stored at four different temperatures of 0,4,15 and 25? was treated with 0.5 ?L·L-11-MCP.The results confirmed that 1-MCP had a delayed effect on the shelf life of kiwifruit at four temperatures,and the lower temperature,the more obvious effect of the retardation.(2)The shelf life quality dynamics model of 'Hayward' kiwifruit was studied in 1-MCP treatment(treatment group)and non-treatment(control group)to predict the shelf life of 'Hayward' kiwifruit.The 0.5?L·-1 1-MCP treatment(treatment group)and the untreated(control group)'Hayward' kiwifruit were stored at 0,4,15 and 25?.The changes in the firmness and Vc content of kiwifruit under four temperature conditions were determined.The shelf life prediction model was established based on Arrhenius formula,and the model was verified by selected 20? samples.The results showed that 1-MCP had a certain retardation on the reduction of kiwifruit firmness,titratable acid and Vc contents,and an increase in soluble solid content under different temperatures.The kinetic equations of Vc content in the control and treatment groups followed the first-order reaction kinetics,the control group R2?0.97,and the treatment group R2?0.94,The kinetic equations of the firmness content changes of the control group and the treatment group followed the zero-order reaction kinetics.The control group R1?0.96,and the treatment group R2?0.92.The fineness of the control group decreased and the Ink of the decrease of Vc and the R2 of 1/T was>0.98,while the firmness of the treated group decreased and the Ink of the decrease of Vc and the R2 of 1/T was>0.90.The verification results showed that the relative error between the predicted and measured values of the kiwifruit in the control group were within±10%;A comprehensive analysis of the two models of the control group showed that the kiwifruit prediction model based on the firmness change was more feasible.Based on the model of Vc content and firmness reduction in the control group,the shelf life of'Hayward' under storage conditions of 20? was 29 days.(3)The suitable date for harvesting 'Hayward' kiwifruit in Wugong County Shaanxi Province'Hayward'which is in Wugong County,Shaanxi Province was test material.It was three times for harvesting(I:SSC was 6.52%,dry matter content was 15.77%,II:SSC was 6.98%,dry matter content was 18.14%,?:SSC was 7.45%,dry matter content was 18.62%)to study the shelf life of storage at 0? and 20?,The results showed that the kiwifruit harvested at the harvesting period II had the longest shelf life at 20?,which was 5 days longer than the shelf life of kiwifruit in harvesting period I and harvesting period III.The kiwifruit of harvesting period II traits were still good after being stored for 135 days at 0?.The firmness and Vc content were the highest at the time of harvesting,and the slowest decrease in the post-ripening softening process,and the weight loss rate increased slowly.Therefore,the comprehensive analysis showed that harvesting period ? was the best one for'Hayward' in Wugong County.(4)50 mg kg-1 of ethephon was used to shorten the post-ripening time of kiwifruit.The 1 uL·L-1 of 1-MCP was used to treat the 'Hayward' when the SSC content reached 10%,12%and 14%.The result showed that 1-MCP was used to treat it when the SSC content reached 12%,and the 'Hayward' post-ripening period was 21 days,and the shelf life was 9-12 days.Compared with the 'Hayward' of the control group,the post-ripening period was 3 days longer and the shelf life of the food was extended by 9 days.