在环境和高温下模拟牛奶粉的水分吸附异温,使用动态露点异温 (DDI) 方法
Erika Kadas1, Abass Oduola1, Peter M Rubinelli1
1Department of Food Science, Center for Food Safety, University of Arkansas System Division of Agriculture, Fayetteville, AR 72704.
JDS communications
|September 9, 2025
概括
奶粉中的水活性是质量的关键. 这项研究使用了动态露点等热法来分析无脂干牛奶 (NFDM) 和牛奶蛋白缩物 (MPC-85) 中的水分吸收,提供了预测质量工具.
科学领域:
- 食品科学 食品科学 食品科学
- 物理化学 物理化学
- 乳制品技术 乳制品技术
背景情况:
- 水的活性对奶粉的质量和安全至关重要.
- 零售商经常使用水分含量作为水活动的代理,因为成本和测量方便.
- 湿度吸附异热体将水分含量与水活动联系起来.
研究的目的:
- 确定无脂肪干牛奶 (NFDM) 和牛奶蛋白缩剂 (MPC-85) 的水分吸附和脱吸等温度.
- 研究环境和高温对这些同热体的影响.
- 将现有模型与数据相匹配,以预测保质期和质量变化.
主要方法:
- 使用了现代化的动态露点同温 (DDI) 方法.
- 在不同温度下确定湿度吸附和脱附等温.
- 应用回归分析,使已建立的模型 (修改的奥斯温,修改的普福斯特,GAB) 与实验数据相匹配.
主要成果:
- NFDM表现出II型吸附异热体,而MPC-85显示出III型.
- 这两种粉末都表现出III型脱吸异热,可能是由于晶体成分.
- 温度显著影响异热体,并观察到歇斯底里,特别是在MPC-85.
结论:
- 修改后的Oswin,Chung-Pfost和GAB模型有效地描述了NFDM和MPC-85.5的吸附行为.
- 奶粉质量受到处理,加工和储存期间的成分和温度的影响.
- 结果为预测和评估各种奶粉的质量提供了工具.
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