预测模型用于冷干燥无形材料的表面化和膨胀
Sukritta Anantawittayanon1, Kiyoshi Kawai1
1Program of Food and AgriLife Science, Graduate School of Integrated Sciences for Life, Hiroshima University, 1-4-4 Kagamiyama, Hiroshima, 739-8528, Japan.
Cryobiology
|July 3, 2024
概括
预测表面温度 (Tsur) 有助于防止冷无形材料的表面化和膨胀. 这项研究开发了一个计算 Tsur 的模型,有助于控制产品的质量和稳定性.
科学领域:
- 食品科学与技术 食品科学与技术
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 在冷干燥无形材料中的表面化和膨胀与表面温度 (Tsur) 和冷缩玻璃过渡温度 (Tg') 之间的差异有关.
- Tsur受溶液类型,度和冷干燥条件的影响,因此预测对于过程控制至关重要.
研究的目的:
- 建立一个基于计算的 Tsur. 的冷干燥无形材料表面化和膨胀的预测模型.
- 为了使 Tsur 的预测能够使用最小的基本参数进行实际应用.
主要方法:
- 提出了一个基于热力学平衡的Tsur预测模型.
- 对糖,马尔托德素及其混合物进行实验确定了特定材料的参数 (Tg',未水含量,真实密度).
- 图尔在各种室内压力 (13,38,103帕) 下计算,并与表面融化和膨胀的实验观测进行比较.
主要成果:
- 当计算的 Tsur 超过 Tg' 时,观察到表面化和膨胀,只有少数例外.
- 在冷干燥样本中,增加的 Tsur - Tg' 差异与较高的水活性 (aw) 相相关,表明由于表面现象导致脱水受损.
- 该预测模型在评估干燥效率和储存稳定性方面表现出有用性.
结论:
- 拟议的模型有效地预测了Tsur,为冷干燥过程中的表面现象提供了洞察力.
- 控制相对于Tg'的Tsur对于防止缺陷和确保冷干燥无形材料的质量至关重要.
- 该模型有助于优化冷干燥过程,以提高产品稳定性和脱水.
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