大豆蛋白/聚乙烯醇薄膜对圣女果保鲜性能研究

以大豆蛋白及聚乙烯醇为原料,以薄膜的抗张强度、断裂伸长率、透光率、阻隔性能及吸水率为评价指标,在室温条件下,分别对圣女果进行裸包处理,市售聚乙烯保鲜膜裹包处理,大豆蛋白/ 聚乙烯醇薄膜裹包处理,纳米SiO2改性大豆蛋白/聚乙烯醇薄膜裹包处理,探讨4种保鲜处理方式对储藏过程中圣女果的失重率、硬度、可溶性固形物含量、总酸含量及VC 含量的影响,以研究大豆蛋白/ 聚乙烯醇薄膜对圣女果的保鲜效果.试验结果表明：在0～7 d内,大豆蛋白/ 聚乙烯醇薄膜在一定程度上可缓解圣女果的腐烂霉变,具有一定的保鲜效果;4种保鲜处理方式的效果依次为,纳米SiO2改性大豆蛋白/聚乙烯醇薄膜〉市售聚乙烯保鲜膜〉大豆蛋白/聚乙烯醇薄膜〉空白对照组;阻隔性能较好的市售聚乙烯保鲜膜对圣女果的保鲜效果略次于纳米SiO2改性大豆蛋白/聚乙烯醇薄膜,故对于果蔬的保鲜而言,并不是使用的保鲜膜的阻隔性能越好,其保鲜效果就越好,而是与果蔬的生理作用匹配度越高的保鲜膜,保鲜效果才越好.

Study of Cherry Tomato Preservation with Soy Protein/Polyvinyl Alcohol Films

By taking soy protein and polyvinyl alcohol as raw materials, with the tensile strength of the film, the elongation at break, transparency, barrier properties and water absorption as the evaluation criteria at room temperature, the weight loss, hardness, contents of soluble solids, VC and total acid of cherry tomato treated respectively by bare packet processing, commercially available polyethylene cling film, soybean protein/polyvinyl alcohol film, soy protein/polyvinyl alcohol film modified by nano-SiO2 were periodically measured during storage in order to investigate the fresh-keeping effects. The results show that within 7 days, soy protein/polyvinyl alcohol film could slow down the decay and mildew of cherry tomatoes and they had better preservation effects. The ranking of preservation effects from high to low is soy protein/PVA film modified by nano-SiO2, commercially available polyethylene plastic wrap, soy protein/PVA film and bare packet processing. Although commercially available polyethylene plastic wrap is with good barrier properties, its preservation effect is slightly inferior to the nano-SiO2 modified soybean protein / polyvinyl alcohol film. With regard to fruits and vegetables, the better barrier properties will not necessarily result in the better preservation effects. The effects depend more on the matching degree of the physiological role of plastic wrap with the specific fresh fruits and vegetables.