Study On Storage Techniques Of Hainan Green Orange

Hainan green orange which is one of the biggest brand of Hainan, has many distinguishing features such as sweet and juicy of fruit, green and thin of pericarp. But the storage time is very short under ambient temperature (about5～7days), which affect economic benefits of green orange’s industry, so it’s very urgent to find an effective way to extend green orange’s storage time and improve economic efficiency. The paper reserched the influence of differeent packing and coating, preservative and temperature on green orange’s storage quality after post-harvest. Finally, a comprehensive technical means which was suitable for green orange’s storage had been studied, and it also provided theoretical basis for future research and application. The main results were as follows:1. With the extension of storage time, green orange’s weight loss and pH value of pericarp were increased; contents of soluble solid, titratable acid and Vc were reduced no matter at ambient temperature (26-30℃) or low temperature (6±1℃) by contrasting storage quality under different temperature. However, low temperature could delay green orange’s quality being bad, maintain freshness degree and consumption of nutrients and water were also slowed down.It showed that storage temperature, humidity, moisture content and diseases were main factor which affect green orange’s quality after post-harvest.2. The effect of polyethylene film was significantly better than other packing methods, such as fruit wax, chitosan preservation solution and so on. Polyethylene film of0.01mm was the best way for packing,whose fresh rate70%higher than control group,and weight lose20.31%lower than control group.3. Preservation effect of imazalil was better than other frequently-used citrus preservatives, such as carbendazim, thiophanate-methyl, prochloraz, and sporgon.The pericarp was green, flavour and organization was much better. The optimal treatment conditions were as follows:soaked about60seconds in the solution of500mg/kg imazalil and1.5%NaHCO3at40℃, then stored under ambient temperature, the fresh rate was92.5%after30days storage.4. The influence of green orange’s preservation was investigated by gibberellin of50mg/kg,75mg/kg and100mg/kg.Gibberellin of50mg/kg whose fresh rate6.7%higher than control group was selected by taking account of fresh rate,and it also had green-maintaining effect. Decreases of soluble solid contents, titratable acid and Vc were slowed down, the synthesis of ethylene were restrained, storage time were extended by this treatment.5. Fresh rate of7℃treated with polyethylene film packing was significantly better than20℃and30℃. The fresh rate difference of3℃,6℃and9℃was very significant. Fresh rate was increased16.7%and33.3%respectively.6. Soaked about60seconds in the solution of500mg/kg imazalil and1.5%NaHCO3at40℃, then stored under3℃temperature, the fresh rate was90%after90days storage, and amount of imazalil residue was not exceeded.