Abstract: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.