冷榨双低菜子粕中蛋白质功能性质的研究

对冷榨双低菜子粕中蛋白质的溶解性、持水性、持油性、起泡性等功能性质进行了研究。结果表明,当热处理温度高于50℃时,菜子蛋白质的溶解性会有所增加;在p H为3和5下,菜子蛋白质的溶解度较低,这说明菜子蛋白具有两个等电点;当盐溶液浓度增加时,在p H为8和10的碱性环境下菜子蛋白质的溶解性不断降低,而在低p H下溶解性变化不显著;与大豆分离蛋白质相比,菜子蛋白质的持水性较差,而泡沫的稳定性和持油性较好,这与蛋白质表面疏水性的大小相关。通过对菜子蛋白质功能性质的分析有利于其在食品加工中进一步的开发利用。

Study on Functional Properties of Protein in Cold-pressed Double Low Rapeseed Meal

The functional properties of protein in cold-pressed double low rapeseed meal was studied. The experiment result indicated that when the heat-treatment temperature was above 50℃, the solubility of rapeseed protein increased; under the pH 3.0 and 5.0, the solubility of rapeseed protein was the lowest, therefore,it concluded that there were two isoelectric point in rapeseed protein solution; When the salt concentration was increased, the solubility of rapeseed protein was decreased un-der pH 3.0 and 5.0, but increased under acidic pH value; compared with the soy isolate protein (sPI), the water-holding capacity of rapeseed protein was lower than sPI, but the fat-binding capacity and foaming stability of rapeseed protein were higher than sPI. The difference in functional properties between rapeseed protein and sPI is depended on the surface hy-drophobicity. By analyzing the functional properties of rapeseed protein, it is conducive to the further development and uti-lization of rapeseed protein in food processing.