米蛋白-海藻酸钠互穿网络水凝胶的制备及性能表征

为满足食品领域目前对于高机械强度水凝胶的需求，本研究以碎米蛋白和海藻酸钠为主要原料，通过热处理和离子交联法制备一种高力学性能的食品级碎米蛋白（RP）-海藻酸钠(SA)互穿聚合物网络（IPN）水凝胶。通过改变米蛋白与海藻酸钠凝胶体系中米蛋白的浓度（80、100、120、140、160 mg/mL）调节IPN水凝胶的力学性能，混合液加热及钙离子交联形成水凝胶后，测定其质构性能、流变性能、白度、溶胀性、含水量等性质。结果表明:随着凝胶体系中碎米蛋白浓度的增大，RP-SA IPN水凝胶的储存模量G'、损耗模量G"和凝胶硬度均增加，当碎米蛋白浓度达到为140 mg/mL时，凝胶硬度增加幅度变小。水凝胶溶胀性先降低后趋于平缓，但水分分布更为均匀。因此，适量的碎米蛋白能对RP-SA IPN水凝胶网络有很好的填充效果，并对水凝胶的形态没有太大的改变，同时可通过调节蛋白的添加量来调节水凝胶的力学性能，该研究为米蛋白在食品领域的应用提供了理论基础。

Preparation and Properties Characterization of Rice Protein-Sodium Alginate IPN Hydrogel

In order to meet the demand of high mechanical strength hydrogels in the food field, broken rice protein and sodium alginate were used as the main raw materials to prepare a food-grade broken rice protein (RP)-sodium alginate (SA) interpenetrating polymer network (IPN) hydrogels with high mechanical properties through heat treatment and ion cross-linking in this study. The mechanical properties of IPN hydrogels were adjusted by changing the concentration of rice protein (80, 100, 120, 140, 160 mg/mL) in the gel system of rice protein and sodium alginate, and the properties of the hydrogels, such as texture, rheological properties, whiteness, swelling and water content, were measured after the mixture was heated and Ca2+ cross linked. The results showed that: With the increase of the concentration of broken rice protein in the gel system, the storage modulus G', loss modulus G" and gel hardness of RP-SA IPN hydrogels increased. When the broken rice protein concentration was 140 mg/mL, the increase of gel hardness became smaller. The swelling property of hydrogels first decreased and then tended to be flat, but the water distribution was more uniform. Therefore, proper amount of broken rice protein could fill the RP-SA IPN hydrogels network very well, and the morphology of the hydrogel was not changed greatly. At the same time, the mechanical properties of hydrogels could be regulated by regulating the amount of protein added. This study provides a theoretical basis for the application of rice protein in the field of food.