加热和中和显著影响pH值变化的处理:关于麦蛋白分离物的案例研究
Anthony Suryamiharja1, Xiping Gong1, Hualu Zhou1
1Department of Food Science and Technology, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, GA 30223, USA.
International journal of biological macromolecules
|July 6, 2025
概括
在性pH下用酸加热麦蛋白分离物 (OPI),可显著提高其在中性pH下的溶解性和稳定性. 这种方法增强了食品应用的OPI功能.
科学领域:
- 食品科学 食品科学 食品科学
- 蛋白质化学 蛋白质化学
- 植物性蛋白质 植物性蛋白质
背景情况:
- 由于其紧的结构,麦球蛋白在中性pH下具有较差的溶解性.
- 性处理与pH值转移相结合,可以改变蛋白质的功能,包括溶解度.
- 具体的加工条件,如加热和中和,需要进一步的研究,以优化植物蛋白质溶解度.
研究的目的:
- 评估加热温度和中和方法 (HCl与酸) 对中性pH的麦蛋白分离物 (OPI) 溶解度的影响.
- 在优化的加工条件下,研究OPI的物理化学变化.
- 评估修改后的OPI的稳定性.
主要方法:
- 麦蛋白分离物 (OPI) 在pH12下处理,加热温度变化,并使用HCl或酸中和.
- 在中性pH下测量OPI溶解度.
- 物理化学表征包括颗粒大小分析,差异扫描热量计 (DSC),片映射和圆形二元化 (CD) 光谱.
- 使用zeta潜能测量来评估OPI的稳定性.
主要成果:
- 简单的pH转移并没有提高OPI溶解度.
- 整合加热 (100°C,30分钟) 与酸中和显著改善并保持在中性pH (70-75%) 的OPI溶解度.
- 物理化学分析揭示了纳米级粒子大小,热变性损失,较小的形成,以及二次结构的改变 (减少β-sheet,增加随机线圈).
- 与加热相结合的酸中和导致了较高的泽塔潜力和与HCl相比提高了OPI的稳定性,长达7天.
结论:
- 在pH12下加热麦蛋白分离物,然后进行酸中和,是一种有效的非酶方法,可以提高其在中性pH下的可溶性和稳定性.
- 该研究提供了关于优化植物蛋白质加工以提高食品配方功能的见解.
- 酸在稳定改性麦蛋白方面比HCl具有优势.
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