可食性大豆分离蛋白膜制备与性质

Preparation and characters of edible film from soy protein isolate

为探索新型生物膜材料的制备,以大豆分离蛋白为基本材料,探究大豆分离蛋白（SPI）、增塑剂（甘油）、还原剂（Na_2SO_3）、乙醇等添加量和处理温度、成膜液pH、成膜介质等条件对膜的完整率、厚度、透光率、水溶率、水蒸气透过系数、透油性等性质的影响。当SPI浓度在2%~6%时,随着添加量的增加,成膜变得容易,但是膜的厚度增加、水蒸气透过系数和透油系数变大、色泽变深。甘油添加量在2%以下可以改善膜的柔韧性,同时降低膜的透气性能和透油性。添加5%的乙醇也可以降低膜的透气性和透油性。添加0.1%的Na_2SO_3可以改善膜的色泽,同时降低膜的透油性。适当提高处理温度和溶液pH可以降低膜的透气性和透油性。

The new biomaterials were produced by soy protein isolate （SPI） as base material. The effects of film property such as film in tegrity, thickness, light transmittance, water soluble, water vapor permeability （WVP） and oil permeability （PO） were investigated by film forming conditions included SPI content, ethanol content, plas ticizer （glycerol）, reducing agents （Na2 SOa）, temperature, pH value of film-forming reagent and medium. With more addition of SPI concentration between 2% to 6%, it was more likely to form film, while the thickness, WVP, and PO of films increased and the film became dark. With no more than 2% addition of glycerol, the flexi- bility of film could be improved, but its WVP and PO were reduced. With the addition of 5% alcohol, the WVP and PO of films were also reduced. The addition of 0.1 % NaeSOa could improve the color of the film and reduce its PO at the same time. It could reduce the WVP and PO of the films by increasing the processing temperature and pH val ue of solution to a certain extent.