不同大豆蛋白对小麦面条加工品质和血糖生成指数的影响

为改善小麦面条品质,在小麦粉中添加大豆蛋白(全脂豆粉、脱脂豆粉、大豆分离蛋白、大豆浓缩蛋白、大豆组织蛋白),以拉伸特性、蒸煮特性、微观结构以及血糖生成指数为评价指标,研究大豆蛋白添加量(0%、5%、10%、15%、20%)对面条加工品质及血糖生成指数的影响。结果表明:随蛋白添加量的增加,脱脂豆粉、全脂豆粉的增加使面条的拉断力呈明显上升趋势,拉伸距离呈先上升后下降趋势,大豆分离蛋白、大豆浓缩蛋白添加量的增加使拉断力呈先上升后下降趋势,拉伸距离呈下降趋势,而大豆组织蛋白的增加使面条拉伸性能均逐渐降低;当大豆蛋白添加量为10%时,混合粉面条拉伸特性较优;五种大豆蛋白的添加均使面条的烹煮损失率及断条率上升,全脂豆粉的增加使面条的吸水率、膨胀率逐渐下降,其余四种均使其上升;微观结构表明,脱脂豆粉和全脂豆粉的添加使混合粉面条的面筋网络结构更加连续均匀,而其余三种大豆蛋白添加量的增加造成混合粉面条微观结构的劣变;利用体外复合酶方法测定GI值,血糖生成指数依次为:小麦粉 > 脱脂豆粉 > 全脂豆粉 > 大豆组织蛋白 > 大豆浓缩蛋白 > 大豆分离蛋白。

Effects of Different Soy Proteins on Processing Quality and Glycemic Index of Wheat Noodle

In order to improve the quality of wheat noodle,soy protein(full fat soy flour,defatted soy flour,soy protein isolate,soy protein concentrate,soy protein tissue)was added to wheat flour. The tensile properties,cooking properties,microstructure and glycemic index were used as evaluation indexes to study the effect of soy protein addition(0%,5%,10%,15%,20%)on noodle processing quality and glycemic index Influence. The results showed that with the increasing of defatted soy flour and full fat soy flour,the tensile strength of noodles increased obviously,and the tensile distance increased first and then decreased. With the increaseing of soy protein isolate and soy protein concentrate,the tensile strength increased first and then decreased,and the tensile distance decreased. While with the increase of soy protein tissue,the tensile properties of noodles decreased gradually. When the contents of soy protein was 10%,the tensile properties of mixed noodle were better. The addition of five kinds of soy protein made the cooking loss rate and broken rate of noodles increased,the increasing of full fat soy flour made the water absorption and expansion rate of noodles decrease gradually,and the other four kinds made it increased. The microstructure showed that the addition of defatted soy flour and full fat soy flour made the gluten network structure more continuous and uniform,while the increasing of the other three kinds of soy protein resulted in the deterioration of the microstructure of the noodles. The GI value of the noodles was determined by in vitro complex enzyme method,and the glycemic index of the noodles was:Wheat flour > defatted soy flour > full fat soy flour > soy protein tissue > soy protein concentrate > soy protein isolate.