水的可用性作为热力学特性和食品固体中的水流动性的描述参数
Tingting Cui1,2, Xukai Wu1, Tian Mou3
1Department of Food Science and Engineering, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, China.
NPJ science of food
|June 14, 2023
概括
低水分食物中的微生物生长取决于水的流动性,而不仅仅是水的活动. 一个新的指标,即水的可用性 (Uw),可以更好地预测酵母菌的生长,帮助食品保存策略.
科学领域:
- 食品科学 食品科学 食品科学
- 微生物学 微生物学
- 物理化学 物理化学
背景情况:
- 低湿度食品中的微生物生长是一个重要的保存挑战.
- 了解水在分子层面的作用对于控制微生物腐烂至关重要.
研究的目的:
- 研究水特性,分子流动性和葡萄糖/乳清蛋白分离物 (WPI) 矩阵中的微生物生长之间的关系.
- 引入和验证一个新的参数,即水的可用性 (Uw),用于评估微生物生长潜力.
主要方法:
- 测量葡萄糖/WPI矩阵的吸水异热和热力学特性.
- 使用放松过程和玻璃过渡温度 (Tg) 分析分子运动.
- 水的特性和流动性与D. Hansenii酵母在各种水活动 (水) 和30°C的生长的相关性.
主要成果:
- 吸附等温体,Tg和放松过程受到aw和WPI含量的影响.
- 微生物生长与水流动性比与水活动 (aw) 更密切相关.
- 高水可用性 (Uw) 与增强的酵母生长率和更快的细胞翻倍时间相关.
结论:
- 水的可用性 (Uw) 为食品矩阵中水的动态状态提供了更准确的热力学描述.
- Uw提供了对水与微生物相互作用的更好理解,改善了食品保存策略.
- 这种方法增强了在低湿度的食品系统中对微生物行为的预测.
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