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乳糖在奶粉中的流动性 奶粉中的乳糖流动性
Armin Afrough1, Pernille Andersen1, Tanja Ninette Angelika Weihrauch1
1Department of Chemistry and Interdisciplinary Nanoscience Center, Aarhus University, Denmark.
Food research international (Ottawa, Ont.)
|March 12, 2026
概括
在存储在潮湿条件下的奶粉中检测到移动乳糖. 通过NMR证明的这种移动性表明乳糖与水相互作用,影响粉末的稳定性.
科学领域:
- 食品科学 食品科学 食品科学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 乳糖是奶粉中的主要碳水化合物,通常处于无形状态.
- 在储存期间,乳糖可以经历结晶并与β-乳糖球蛋白等蛋白质发生反应,这些过程需要分子流动性.
- 乳糖在奶粉中的流动性证据有限.
研究的目的:
- 为了研究不同储存条件下的奶粉中的乳糖流动性.
- 为乳糖分子运动提供证据,以应对湿度等环境因素.
- 了解乳糖流动性对奶粉稳定性和相互作用的影响.
主要方法:
- 魔术角度旋转 (MAS) HNMR光谱检测分子运动.
- 2D T1-δ1H在MAS下进行实验,研究放松时间和与水的相互作用.
- 2D H-C HSQC MAS实验以确认乳糖的分子身份和状态.
主要成果:
- 特定的NMR信号 (3.54.0 ppm) 表示乳粉中的移动乳糖暴露在潮湿的空气中.
- 移动乳糖的纵向放松时间常数 (T1) 与水相似,表明接近和交叉放松.
- 1H-13C HSQC光谱证实脱脂奶粉中的移动物种表现出溶液状态乳糖的光谱特征.
结论:
- 暴露于潮湿的空气会诱导牛奶粉中的无形乳糖的流动性.
- 移动乳糖在物理上与水分子非常接近,促进交叉放松.
- 这些发现突显了储存条件对乳糖行为和奶粉潜在降解途径的影响.
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