谷氨酰胺转移酶对食物蛋白质成膜性能的影响

Effect of Transglutaminase on Properties of Cast Films from Food Proteins

研究了添加谷氨酰胺转移酶(TGase)对大豆分离蛋白(SPI)、酪蛋白酸(NaCN)、明胶、乳清蛋白浓缩物(WPC)、小麦面筋蛋白(WG)及花生分离蛋白(PPI)6种蛋白质成膜特性的影响.研究结果表明:在成膜溶液中加入TGase,蛋白质膜的抗拉强度和表面疏水性有不同程度的改善,其中WG,SPI,NaCN和明胶这4种蛋白质膜的抗拉强度分别增加36.2%,17.7%,13.1%和25.6%(P≤0.05);NaCN,SPI,WPC,WG和明胶这5种蛋白质膜的表面疏水性分别增加216.1%,116.9%,30.5%,26.4%和2.4%(P≤0.05);同时膜的水分含量、总可溶性物质量及透光率也明显降低;明胶膜、NaCN膜和WPC膜的断裂伸长率分别增加16.3%,72.6%和172.3%,SPI膜和WG膜的断裂伸长率则分别降低7.5%和36.2%.电泳分析表明TGase使6种蛋白质均产生了共价交联.

The effect of transglutaminase （TGase） treatment on the properties of the cast films from several food proteins including soy protein isolate （SPI）, sodium caseinate （NaCN）, gelatin, whey protein concentrate （WPC）, wheat gluten （WG） and peanut protein isolate （PPI） were investigated. The results indicate that TGase treatment of the film-forming solutions significantly increases the tensile strengths of WG, SPI, NaCN and gelatin films respectively by 36.2% , 17.7% , 13.1% and 25.6% （P≤0.05）, enhances the surface hydrophobicities of NaCN,SPI, WPC, WG and gelatin films respectively by 216. 1%, 116.9%, 30.5%, 26.4% and 2.4% （ P ≤0. 05 ） , and results in the decrease in the water content, the total soluble matter and the transparency for all films. Also, it leads to an increase in the elongation at break by 16.3% ,72.6% and 172.3% respectively for gelatin, NaCN and WPC films, and a decrease in the elongation at break by 7.5% and 36.2% respectively for SPI and WG films. Moreover, a cross-linking induced by TGase is finally confirmed by SDS-PAGE analysis.