不同提取pH条件下火麻仁蛋白组分的功能性质研究  

Research on functional properties of hemp seed protein components in different extraction pH

作　　者：李乐[1,2] 吴晖[2] 赖富饶[2] 

机构地区：[1]重庆化工职业学院应用化学系,重庆400020 [2]华南理工大学轻工与食品学院,广东广州501640

出　　处：《食品与机械》2014年第2期16-19,39,共5页Food and Machinery

摘　　要：采用碱提酸沉的方法确定不同提取pH条件下得到的火麻仁蛋白组分的等电点,并对其相关的功能性质进行研究。结果表明:提取pH分别为8.5,9.5,11.0,11.5时,相应的火麻仁蛋白组分的等电点为3.5,4.0,5.0,5.5。然而pH为8.5时,蛋白质得率较低,不利于后续试验的进行;pH为11.5时,得到的蛋白质为黄褐色,气味较难闻,不利于得到优质的蛋白质。对不同pH提取得到的蛋白质进行溶解性、持水能力、起泡性和泡沫稳定性进行研究,发现提取pH为9.5和11.0时得到的蛋白质溶解性较好,而持水能力没有太大的差异。由于溶解度的不同,环境pH越接近等电点,起泡性越差,而对应的泡沫稳定性越好,这与蛋白质之间的分子排斥力有关。Alkali extraction-acid precipitation method was used to de- termine the protein isoelectric point of hemp seed meal under the dif- ferent extraction pH. The results showed that the isoelectric points were 3. 5, 4. 0, 5. 0 and 5. 5, with the corresponding extraction pH 8.5, 9.5, 11.0, 11.5, respectively. The protein yield was low with the extraction pH 8.5, while the protein was yellow-brown and smelly with the extraction pH 11.5. The protein solubility, water- holding capacity, foaming ability and foam stability were researched, and found that the protein solubility of extraction pH in 9. 5 and 11.0 were good, and water-holding capacity for four pH condition had a little difference. Because of the different solubility, with environ- mental pH closer to the isoelectric point, the foamability was worse. While, the foam stability was better, this may be for the repelling force among protein molecules.

关 键 词：火麻仁 等电点 溶解性 持水能力 起泡性 泡沫稳定性 

分 类 号：TQ914.1[化学工程]