离子交换法制备低植酸含量大豆蛋白的研究

Preparation of Low-phytate Soy Protein by Ion Exchange

大豆食品中的植酸会阻碍多种矿物离子及蛋白的吸收,为了提高大豆蛋白的营养吸收性,加工中应去除植酸。本文研究了离子交换法脱除大豆分离蛋白中植酸的方法和效果,并进一步考察了处理后大豆蛋白的理化性质。结果表明:透析、超滤与离子交换法进行比较,阴离子交换后植酸含量下降77%,较优于其他方法。后采用离子交换法去除大豆蛋白中的植酸,对不同树脂、不同蛋白状态及酸碱度对植酸的去除效果进行比较,以确定植酸去除的最优方案。与其他树脂相比,D201树脂对植酸的吸附率达到12 mg·m L-1,在p H7.0的条件下可将植酸含量降低到1 mg·g-1,下降约90%。制备的低植酸含量的大豆蛋白等电点向右偏移,溶解性略有下降,分散速度有所提高。

Phytic acid in soybean food can affect the absorption of many mineral and protein. In order to improve the nutrient absorption of soy protein, phytic acid should be removed in processing. This paper studies the method and effect of removing phytic acidin soybean isolated protein by ion exchange method, and also the physical and chemical properties of soybean pro- tein after ion exchange processing. The methods of dialysis, uhrafihration and ion-exchange are compared, the method of anion exchange decrease the content of phytic acid by 77% , which is superior to other methods. An optimal phytate removing method was chosen by comparing the phytate removing effect in different kinds of resins, protein stages and pH values. The results showed that the resin adsorption rate of D201was as high as 12 mg ~ mL-＇ resin. Under the condition of pHT, it could reduce the phytate level by 90% to a concentration of 1 mg · g-i protein. Isoelectric point （pI） of the low-phytate soybean protein showed a right shift, with a decreasing solubility and an increasing dispersion speed.