Study On The Degradation Mechanism Of Chlorophyll During Storage And Factors On Stabilization During Process Of Kiwifruit

Kiwifruit is a kind of popular fruit which is accepted by mostly customer for its nourishment. It is getting research hotspot recently for its green pulp and high chlorophyll contents."Qinmei"Kiwifruit was as the material of experiment , in 0℃±1℃, studied on the relativity between the law of chlorophyll catabolism and fruit quality, active oxygen, membrane lipid peroxidation, cell wall ultrastructure, chloroplast ultrastructure during senescence. Studied on the effect of different factors to the contents of chlorophyll during processing. All the results are showed below:(1) kiwifruit belonged to"early apex"with ethylene apex present ahead full ripe; kiwifruit could be keep fresh about 75days in 0℃±1℃.(2) In 0℃±1℃,the contents of chlorophyll and firmness were terribly significant plus relativity, with SSC terribly significant negative relativity, with pH value significant negative relativity ,with Fv/Fm significant plus relativity. So firmness, SSC, pH value and Fv/Fm were all as the indicative index of chlorophyll change.(3) Active oxygen and its enzyme system both entered into catabolism of kiwifruit chlorophyll during cold-storage , the accumulation of O₂^-·could accelerate the speed of chlorophyll catabolism, activity of SOD increased, the speed of chlorophyll catabolism was slowed; but POD had double effects to chlorophyll catabolism; contents of MDA and chlorophyll were significant negative relativity, related coefficients was to 0.93.(4) Activity of chlorophyllas and Mg-dechelatase were apex changes, while the activity of enzymes was high, the speed of chlorophyll catabolism was accelerated.(5) Cell wall of kiwifruit losed its intrinsic structure in cold-storage 90 days, in 60 days chloroplast was already disintegration, structure disintegration damaged the space separation between chlorophyll and enzyme of chlorophyll catabolism, so the possibility of chlorophyll catabolism was accelerated.(6) In process condition ,the effects of temperature and pH to A* value, chlorophyll and Vc contents had very significant difference(p<0.01);within 48 hours, the different conditions of illumination and air had no significant difference to A* value, chlorophyll and Vc contents; while the temperature of float burn was high and time was long, POD losed its more activity, while the temperature were 90℃,95℃,100℃, the time exceeded 1 minute, then the mostly activity of POD had been losed.