| Currently the fresh-keeping film for fruits and vegetables is mainly plastic, it can not be naturally degraded, and also there will be hidden danger for health and safety of people. In order to solve this problem, people also launched paper packaging products and biodegradable plastics materials, but because the cost is high, the price is expensive,it is hard-promoted. Therefore, it has been a long-term research hotspot to seek a kind of material that has good performance of plastic, is biodegradable, and do not threat people's health. Polysaccharide films are easy-biodegradable and has good performance, which is good substitute product for the plastic wrap and gradually has caught people's attention. This study chooses Konjac Konjac glucomannan chitosan (Portuguese Kennedy, referred to as KGM) for the materials, chooses kara glue (Carrageenan) for complex materials, Konjac Portuguese Kennedy with chitosan/Carrageenan membrane, it made tensile strength, the folding, elongation and membrane WVP as evaluation indexes, to discuss KGM dosage, KGM/Carrageenan ratio, glycerin dosage, pH value, the drying temperature of konjak factors such as Portugal Carrageenan gump with chitosan/film properties determine the effect of compound film, so we could get the optimum technological conditions for membrane technology and provides important reference data for the key technology and parameters of the process, The research also study the effect of fresh-keeping film appling to mango, the results of the study are as follows:1 After purification, tensile strength of the membrane that made of Konjac glucomannan increased more than doubled comparing with before, and its folding endurance increased 60%. This is mainly because konjac's purification improve the binding extent of the Portuguese Kennedy KGM chitosan molecules, the combination between the molecules of the force is also add.2 KGM's dosage, the proportion of KGM and kara glue, pH conditions, the addition of glycerin, the drying temperature of KGM complex film has great influence in tensile strength, elongation rate, and the WVP aspects of performance. Influence factors of membrane performance of orthogonal test, and the compound membrane comprehensive analysis and evaluation of the film, the optimum technological conditions:KGM dosage 0.55 g, KGM/carrageenan ratio for 3 pH9.0 0.65 dosage, glycerin,55 degrees Celsius temperature, dry mL.3 Using mixed membranes were fresh-keeping of mango, KGM inspection with the actual use of the film, and plastic film with fresh, the group did not use any blank, and the results showed that the film compound membrane treatment can effectively reduce the storage period in mango, physiological and biochemical activity slowed mango anaerobic respiration, good effect. In the end, the storage period with membrane can significantly reduce the storage period of weightlessness rate mango, abate respiratory strength and delay the peak respiratory, Vc, total acid nutrient loss also can maintain at a low level. Rotten fruit relative blank group for 25%, complex film can be rotten fruit rate of mango finally in 2.9% of control within. After treatment with film, mango fruit of PPO, POD activity increase in the smaller, SOD activity during storage, can maintain less decline is smooth level, PPO, POD and SOD activity of enzyme etc. Had better inhibition, reduce the storage period in the mango Browning level, and greatly improve the quality of the mango and commercial value. With better effect of preservation in plastic film, especially in fresh fruit, fruit rot disease rate and reduce reduced respiration intensity during fruit storage etc, to use effect was better than plastic film, is able to keeping fresh of film to replace plastic materials ideal, the potential commercial value considerable and broad prospects.
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