Effects Of 1-MCP Treatment On Quality, Physiologies Of Softening And Senescence Of Carambola Fruit During Storage

Carambola (Averrhoa carambola L.), which could be called starfruit as well, was one of the most important southern tropical fruits. It was widely distributed in Guangxi, Fujian, Taiwan and Hainan provinces. Because of its thin skin with brittle five edges, it was extremely easily damaged and resulted in rotting edges, which maked postharvest marketing and preservation difficult. At room temperature, with no technological packaging it would decay soon and could only last a week. This study adopted AnsiP, which was a new anti-ethylene product of Taiwan LiTong company. XiangMi carambola was picked from a farm in Zhangzhou city, FuJian province. After processing, stored in the condition of (15±0.5)℃, 90% relative humidity. Conclusions were obtained as follows:1. Experiment adopted 0.3μL/L, 0.6μL/L, 0.9μL/L three concentrations of 1-methylcyclopropene (1-MCP) to treat XiangMi carambola fruits. After being processed with 1-MCP, XiangMi carambola fruits could be significantly different (P<0.05) from unprocessed fruits in weight loss rate, pulp hardness, sound fruit rate and rate of cell permeation. Besides, chlorophyll content, acid content in processed fruits were higer than the controls. Through the experiment, we found obvious difference between these concentrations, among them 0.6μL/L was the best choice.2. Studied the effect of opptimal concentration 0.6μL/L on carambola nutritional quality and physiological function. It told us that respiration intensity of processed fruits was significantly greater than the controls, and the breathing peak also had been postponed by the time. It could be inferred from experimental results that carambola was a respiration climacteric fruit. Meanwhile, this treatment had good effect in protection of nutrition and quality.3. Experiment showed that 0.6μL/L of 1-MCP treatment significantly inhibited the softening of the fruits. The content in cell wall of carambola fruit, including original pectin, cellulose and hemicellulose was significantly (P<0.05) higher than those in the control group. PG and Cx activity were closely related to fruit softening, they could be inhibited effectively. 4. When the fruit reached senescence, its cell membrane permeability and MDA content would increase. The result showed that 1-MCP treatment could postpone the fruit senility. The malondialdehyde content(MDA), relative conductivity, superoxide anion producing rate were given significant inhibition. Explained the truth that the degree of lipid peroxidation was lighter than the controls. Meanwhile, related enzymes in active oxygen metabolism including POD, SOD, CAT, APX were also got activated.