Research On Postharvest Physiology And Storage Technology Of Navel Orange

Taken Newhall Orange (Citrus sinensis ’Newhall’) of Yunnan Jianshui as test materials, combined with the production requirement, through study the key factor about pre-storage, controlled atmosphere, anti-corrosion coating preservation and preservative. Research the effects of pre-storage time, CO2concentration in CA, chitosan coating preservation and MAP films on navel orange preservation. Provide theoretical basis of navel orange preservation to maintain storage quality and extend storage period.(1) Effect of pre-storage. Study the effect of different pre-storage conditions (38±2℃, relative humidity (RH) of95%, pre-storage during2d,4d,6d) on navel orange, resulted that pre-storage treatments during4d, reducing the respiration rate of navel during storage effectively. Storage after150d, the weight loss percentage was4.26%, decay percentage was12.90%, which maintain the quality and reducing the dry granulation of navel orange excellently.(2) CO2damage threshold. Orange which classified under4℉, O2:4-5%atmosphere storage, regulating the CO2concentration (1%,3%,5%,7%). Experimental results as4-5%of O2,3%of CO2could maintain the quality of navel orange and prolong the storage period after150d under4℃. In the end of storage, the SSC of orange reached at11.20%, Vc content was33.98mg/100g. CO2damage threshold was above5%, that is, when CO2concentration gets7%, the edema disease of navel orange was appeared.(3) Effect of chitosan hydrogel coating. Study the inhibitory effect of Penicillium on navel orange harvest in different chitosan hydrogel concentrations (1.0%,1.5%,2.0%,2.5%,3.0%), considering decay rate, weight loss and nutritional ingredients in storage period of navel orange which coating. It indicated that when the concentrations of chitosan was2%, the effect of suppressing Penicillium is best, the reduction of fruit decay rate, respiration rate and weight loss are lower during4℃storage. Also, it had the best quality of orange after storage150days.(4) Best preservative. The study of antibacterial effect of pencillium for navel orange among the four preservatives which natamycin, prochloraz, carbendazol and bellkute. Shows that the effect of natamycin among four preservatives is best. The navel orange which treated by natamycin for150days had a better appearance and taste, the SSC of orange reached at11.50%, Vc content was33.65mg/100g. Also have a lower decay percentage and injury ratio.(5) Best MAP films. At the same storage temperature (4℃), different effects of navel orange MAP are:0.025mm thick PE>0.015mm thick KDM>0.12mm thick PVC.0.025mm thick PE packaging orange can effectively inhibit respiration, without producing CO2 gas damage, the equilibrium concentration in the gas bags is O217.70%, CO24.20%, delaying the aging process ripe of orange and prolong their shelf-life.In summary, the navel orange integrated preservation technology mode:natamycin dip fruit about30s, at38±2℃, relative humidity (RH) of95%, pre-storage4d,0.025mm thick PE film packaging, control the gas concentration O2:4-5%, CO2<3%-5%, at4℃, RH85%-90%low temperature storage, the best storage time is150d.