Mun Saehun, Surh Jeonghee, Shin Malshick
Center for Food and Bioconvergence, Seoul National University, Seoul, 08826 Republic of Korea.
Department of Food and Nutrition, Kangwon National University, Samcheok, 25949 Republic of Korea.
Food Sci Biotechnol. 2020 Jul 25;29(10):1401-1406. doi: 10.1007/s10068-020-00799-3. eCollection 2020 Oct.
Dispersion of rice protein (RP) at a neutral pH is highly important for its application in the food industry. We analyzed the solubility of RP at different pH conditions and found higher solubility at pH < 3 and pH > 8 than at a neutral pH. Furthermore, at pH 2, the RP solubility improved from 30 to 63% with sonication; however, the samples precipitated when the pH was increased from 2 to 7. To circumvent this, anionic pectin and sodium alginate were added to the RP solution at pH 2. Pectin formed a complex with RP at pH 2, showing a shift in the zeta-potential from 17.3 mV (RP only) to - 1.0 mV (RP plus 1% pectin). Interestingly, the formation of this RP-pectin complex allowed RP to remain dispersed when the pH was increased to 7. Moreover, a stable emulsion could be prepared using the RP-pectin complex as an emulsifier.
大米蛋白（RP）在中性pH值下的分散性对其在食品工业中的应用极为重要。我们分析了RP在不同pH条件下的溶解度，发现其在pH < 3和pH > 8时的溶解度高于中性pH值时。此外，在pH 2时，经超声处理后RP的溶解度从30%提高到了63%；然而，当pH从2增加到7时，样品会沉淀。为了避免这种情况，在pH 2的RP溶液中加入了阴离子果胶和海藻酸钠。果胶在pH 2时与RP形成复合物，zeta电位从17.3 mV（仅RP）变为 -1.0 mV（RP加1%果胶）。有趣的是，这种RP-果胶复合物的形成使RP在pH增加到7时仍能保持分散。此外，使用RP-果胶复合物作为乳化剂可以制备稳定的乳液。
