孔腔形状问题 - 通过4D XCT方法对冷干燥动力学进行现场调查
Sebastian Gruber1, Joshua Greiner1, Alexander Eppink2
1Technical University of Munich, School of Life Science, Department of Life Science Engineering, Food Process Engineering, Weihenstephaner Berg 1, 85354 Freising, Germany.
Food research international (Ottawa, Ont.)
|August 19, 2024
概括
了解食物的微观结构,包括毛孔大小,形状和方向,是优化冷干燥的关键. 这项研究揭示了孔隙导向显著影响了升华时间,这对于有效的食品保存至关重要.
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:
- 冷干燥可以延长食品的保质期,但耗费大量时间和精力.
- 更高的货架温度加速冷干燥,但有可能损坏产品.
- 产品的微观结构在冷干燥过程中极大地影响热量和质量传输.
研究的目的:
- 为了研究3D结构参数对冷干燥动力学的影响.
- 分析毛孔大小,形状和方向如何影响升华.
- 通过了解微观结构与属性关系来优化冷干燥的效率.
主要方法:
- 在马尔托德克斯特林溶液上进行冷干燥实验.
- 使用4D-X射线计算机断层扫描 (XCT) 进行现场可视化.
- 不同的溶液度和货架温度 (-11°C, -15°C, -33°C).
主要成果:
- 证明了微观结构在冷干燥动力学中的关键作用.
- 鉴定出孔隙方向是化时间的重要因素,特别是在纵向孔隙.
- 强调需要进行详细的微观结构分析,以优化流程.
结论:
- 优化冷干燥需要对产品的3D微观结构有深入的了解.
- 孔径方向是控制升华速率的关键参数.
- 详细的微观结构特征可以导致更高效和更少的破坏性冷干燥过程.
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