The Control Of MA Cold Storage In Nectarine Fruits During Ripening And Softening

The effects of MA cold storage on respiration rate, the rate of ethylene production, thevariation of cellwall substance (cellulosepectin), the activities of amylase correlated withsoftening (PG,CX) and the qualities of "Qinguang2hao"nectarine fruits during ripeningand softening were studied in this thesis. The functionary mechanism of MA cold storageinhbiting nectarines ripening and softening were also discussed, which provided theoreticalbases and technical reference for MA storage applying to fruits storage. The results of study showed that (1)'Qinguang2hao'nectarine is the typicalclimacteric fruit, it had great respiration peak and ethylene peak. MA cold storage couldsignificant reduce the ethylene production, and delayed the appearing time of ethylenepeak for 5days.It postphoned the appearing time of respiration peak and inhibited theascent of respiration rate,too. (2) There were remarkable effects on fruit firmness and weight loss. MA cold storageretarded the begainning time of firmress and weight loss for 10d. (3) To some extent, MA cold storage restrained the hydrolysis of cellulose and pectinand the increase of the amylase activities relating to fruit softening like PG and CX , so theripening and softening of the nectarine fruits was retarded to 60d, as well as lowed therelative membrane permeability. (4) MA cold storage made for keeping the nectarine fruits qualities, it prolonged thevariation process in Vc, titratable acidity, water-soluble protein, chlorophyl content andcolour changes. But there was no remarkable effect on the changes of TSS content. It indicated that MA cold storage could delayed the nectarine fruits ripening andsoftening ,so extend the post-harvest shelf life.