亚临界水萃取米糠蛋白工艺与功能特性研究

Optimization for the Extraction and Function Characteristics of Protein from Rice Bran by Subcritical Water

以米糠蛋白提取率为指标,通过单因素和正交试验,优选出米糠蛋白的亚临界水萃取工艺参数并对其功能特性评价。结果表明,压力为8.0 MPa、体系pH值9.0、萃取温度200℃、水料比15 mL/g、提取时间25 min时,米糠蛋白提取率达55.9%,其蛋白乳化活性为119.8 mL/g,乳化稳定性为81.3 min,起泡性为71.5%,起泡稳定性为37.4%,持水性为5.6%,持油性为3.7%,溶解度为68.4%。与碱水浸提法和超声波辅助碱水提取法相比,米糠蛋白的亚临界水萃取法在提取时间和提取率方面均具有明显的优势(碱水提取法和超声波辅助碱水提取法的提取时间和提取率分别为120 min、35.6%和30 min、48.1%)。

With the aim to optimize the technology parameter of subcritical water extracting protein from rice bran,the single factor and orthogonal experiments were conducted by taking protein yield as index,and the function characteristics of protein from rice bran were studied.The results were as follows： the ratio of protein in the extracts was 55.9% at 8.0MPa,pH value 9.0,200℃ for 25min with the liquid-solid ratio of 15mL/g,the emulsion activity index of rice bran protein was 119.8mL/g,and the emulsion stability indicator was 81.3min;the foamability and the stability of foam were 71.5% and 37.4% respectively;the water/oil absorption and the solubility were 5.6%,3.7% and 68.4% respectively.The extract time and the protein yield of rice bran extracted by the methods of alkaline water and ultrasonic assisted alkaline water were 120min,35.6%,and 30min,48.1% respectively.Compared with the previous two methods,subcritical water extracting protein from rice bran has obvious advantage in saving time and extraction ratio.