微波辅助Osborne法提取米糠谷蛋白及对其性质的影响Microwave-assisted Osborne extraction of rice bran gluten and its properties

Abstract

米糠中蛋白质含量丰富，蛋白的必需氨基酸组成也比较完整，是一种优良的蛋白资源，因其组成成分复杂，难于提取。为了更加有效地提取米糠谷蛋白，采用微波辅助Osborne法提取米糠谷蛋白，通过单因素试验研究微波功率、微波时间、微波温度对米糠谷蛋白提取率的影响，在此基础上采用正交试验确定最优提取条件，同时研究了微波处理对米糠谷蛋白结构和功能性质的影响。结果表明：在微波功率800 W、微波时间15 min、微波温度40 ℃的条件下，米糠谷蛋白提取率为73.1%。微波处理后，米糠谷蛋白的α-螺旋和β-转角向β-折叠转移，β-折叠含量明显提高。经过微波处理后，米糠谷蛋白的溶解性提高了8.12百分点，持水性提高了0.89百分点，起泡性增加了20.41百分点，乳化稳定性增加了550百分点。随着微波功率的增加，米糠谷蛋白表面疏水性总体增加。适当的微波处理能有效地增加米糠谷蛋白提取率并改善米糠谷蛋白的部分功能性质。研究结果为米糠谷蛋白的工业化制备及在各种食品配方中的应用提供理论支撑。 Rice bran is rich in protein, and the essential amino acid composition of the protein is relatively complete. It is an excellent protein resource. However, it is difficult to extract protein from rice bran because of its complex components. In order to extract rice bran gluten more effectively, the microwave-assisted Osborne method was used, and the influences of microwave power, microwave time and microwave temperature on the extraction rate of rice bran gluten were studied by single factor experiment, then the extraction conditions were optimized by orthogonal experiment. The effects of microwave treatment on the structure and functional property of rice bran gluten were also studied. The results showed that under the conditions of microwave power 800 W, microwave time 15 min and microwave temperature 40 ℃, the extraction rate of rice bran gluten was 73.1%. After microwave treatment, the α-helix and β-turn of rice bran gluten transferred to β-sheet, and the content of β-sheet increased significantly. Compared with natural gluten, after microwave treatment, the solubility of protein increased by 8.12 percentage points, the water holding capacity increased by 0.89 percentage points, the foaming property increased by 20.41 percentage points, and the emulsion stability increased by 5.50 percentage points. With the increase of microwave power, the surface hydrophobicity of rice bran gluten increased totally. Proper microwave treatment could effectively increase the extraction rate of rice bran gluten and improve some functional properties of rice bran gluten. The research results provided theoretical support for the industrial preparation of rice bran gluten and its application in various food formulations.

Keywords

• 米糠谷蛋白；微波辅助提取；功能性质；结构
• rice bran gluten; microwave assisted extraction; functional property; structure