| 摘要: |
| 【目的】研究大豆种类、凝固酶种类及反应条件对大豆蛋白凝胶特性的影响。【方法】选择6种优质大豆品种吉农 34、吉农 28、吉农18、吉农 17、吉农芽豆及北豆28，对其大豆蛋白质含量及凝胶强度进行分析;然后以未添加酶组为空白对照，分析加入转谷氨酰胺酶、碱性蛋白酶、中性蛋白酶、木瓜蛋白酶对大豆蛋白凝胶强度的影响;并通过响应面优化试验与Design-Expert8.0数据处理软件,对高强度大豆蛋白凝胶的制作工艺进行优化;通过扫描电镜和圆二光谱，对转谷氨酰胺酶作用前后大豆蛋白的凝胶构象进行表征。【结果】6种大豆中，吉农芽豆的蛋白质含量最高，凝胶特性最强。4种蛋白酶中，以转谷氨酰胺酶对大豆分离蛋白凝胶强度的提升效果最为明显。对高强度大豆蛋白凝胶制作工艺的优化结果表明，在转谷氨酰胺酶添加量为34.67 U/g、反应时间2.21 h、反应温度60 ℃、pH为7.22的条件下，大豆蛋白的凝胶强度达到最大，为181.779 g·mm。通过扫描电子显微镜观察、CD图谱分析及Reed拟合计算可知，转谷氨酰胺酶作用前后大豆蛋白的表观结构、二级结构及三级结构均发生了明显变化。【结论】转谷氨酰胺酶对大豆蛋白形成凝胶具有促进作用，其通过使大豆蛋白结构发生变化来实现。 |
| 关键词: 大豆蛋白 凝胶特性 转谷氨酰胺酶 响应面优化 CD图谱 Reed拟合 |
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| 基金项目:吉林省高等学校秸秆综合利用高端科技创新平台项目（吉高平合字［2014］C-1）；吉林省教育厅科研项目（吉教科合字［2014］第609，吉教科合字［2014］第546） |
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| Influence of transglutaminase on soybean protein gel preparation and structure |
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ZANG Xueli,CHEN Guang
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| Abstract: |
| 【Objective】The effects of soybean varieties,enzyme types and reaction conditions on properties of soy protein gels were studied in this paper.【Method】Six high-quality soybean varieties including Jinong 34,Jinong 28,Jinong 18,Jinong 17,Jinong sprouted broad bean and Beidou 28 were selected,and protein content and gel strength of soybean were analyzed.The effects of adding transglutaminase,alkaline protease,neutral protease and papain on the gel strength of soybean protein were analyzed and the control group added no enzyme.The preparation of high-strength soybean protein gel was also optimized by response surface optimization and Design-Expert8.0 data processing software,and the conformation of soybean protein gel was analyzed by scanning electron microscopy and circular dichroism before and after transglutaminase treatment.【Result】The contents of protein of Jinong sprouted broad bean were the highest with the strongest gel characteristics among the six soybeans.Among the four proteases,transglutaminase was the most effective to enhance the gel strength of soybean protein isolate.The optimum conditions for preparation of high strength soy protein gel were enzyme concentration of transglutaminase 34.67 U/g,reaction time 2.21 h,reaction temperature 60 ℃ and pH value 7.22.The obtained highest gel strength was 181.779 g·mm.The apparent structure,secondary structure and tertiary structure of soybean protein changed significantly after transglutaminase treatment through scanning electron microscope,CD map analysis and Reed fitting calculation.【Conclusion】Transglutaminase could promote the formation of soybean protein gel by changing the structure of soybean. |
| Key words: soybean protein gel preparation transglutaminase response surface optimization CD map Reed fitting |
