不同pH下阿魏酸对大豆分离蛋白膜性能的影响  

The Effect of pH and Ferulic Acid on Selected Properties of Soy Protein Isolate Films

作　　者：包惠燕[1] 郭乾初[2] 欧仕益[1] 李爱军[1] 杨爱华[1] 

机构地区：[1]暨南大学食品科学与工程系,广东广州510632 [2]香港理工大学应用生物与化学科技系

出　　处：《食品科学》2004年第9期67-70,共4页Food Science

摘　　要：本文报道了阿魏酸、pH及碱液等对大豆分离膜的的影响。以大豆分离蛋白为主要基质的成膜溶液调pH、热处理后铺板干燥,揭膜,在相对湿度为52%的室温环境下平衡48h后测定膜的抗拉强度、断裂伸长率、水蒸气透性、颜色等。结果表明,大豆蛋白膜的断裂伸长率随pH的升高而增加,抗拉强度在中性pH以上时也是随pH升高而增加;阿魏酸的添加可显著增加膜的拉伸张力和断裂伸长率,但也使膜的颜色变深;阿魏酸还使我们可以在成膜溶液pH为中性时制备具有较强抗拉强度的膜:加阿魏酸100、200、300mg( 此用量分别相当于大豆分离蛋白的2%、4%、6%)将成膜溶液pH调为7.0,与对照相比,可使断裂伸长率提高24.2%～54.4%,抗拉强度提高62.5%～94.3%。This study was conducted to determine the effect of ferulic acid on selected properties of glycerol-plasticized soyprotein isolate (SPI) films. Films were plate casted from heated (80℃ for 30 min) neutral or alkaline aqueous solutions of SPI(5g/100 ml water) , glycerol (2.5g), and ferulic acid (0, 100, 200, 300mg), and dried in an oven at 50℃. Tensile strength (TS),percent of elongation at break (E) , color values ( L, a, and b) , and water vapor permeability (WVP) were examined afterconditioning film specimens at 25℃ and 52% relative humidity (RH) for 2d. The use of ferulic acid resulted in the increase inboth E and TS to different extents at different pHs. The addition of ferulic acid made it possible to prepare SPI films from neutralfilm-forming solutions: compared with control films without ferulic acid, the addition of 100～300mg ferulic acid resulted in anincrease of TS from 62.5% to 94.3%, and an increase of E from 24.2% to 54.4%. Increased darkness, redness and yellowness asevidenced by smaller L values and greater +a and +b values were noted for films with high amounts of ferulic acid. Nodistinguished positive effect of ferulic acid on the WVP of the films was found.

关 键 词：阿魏酸 PH 碱液 膜性能 大豆分离蛋白膜 机械特性 水蒸气透性 

分 类 号：TS214[轻工技术与工程—粮食、油脂及植物蛋白工程]