干燥玉米的破裂机制的调查:由温度梯度驱动的多尺度变化
Wenchao Liu1,2,3,4, Xinyu Wei5, Nan Zhang1
1College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, China.
Journal of food science
|June 24, 2025
概括
优化玉米的热空气干燥温度 (40°C-80°C) 是关键. 中等温度 (60°C-70°C) 平衡水分迁移,减少压力,尽量减少裂,提高质量.
科学领域:
- 农业工程 农业工程
- 食品科学 食品科学 食品科学
- 材料科学 材料科学 材料科学
背景情况:
- 热空气干燥对于玉米的保存至关重要.
- 了解干燥引起的应力和微观结构变化对于质量控制至关重要.
- 以前的研究尚未完全阐明将干燥温度与玉米核完整性联系起来的分子机制.
研究的目的:
- 调查热空气干燥温度对玉米核水分迁移,裂形成和微观结构变化的影响.
- 阐明干燥温度,内部湿度梯度,热应力和裂纹发展之间的关系.
- 提供分子层面的了解,干燥如何影响玉米粉和蛋白质结构.
主要方法:
- 多级特征技术包括低场核磁共振 (LF-NMR),扫描电子显微镜 (SEM) 和里埃变换红外光谱 (FTIR).
- 热空气干燥温度从40°C到80°C的系统变化.
- 分析水分迁移,裂形成和微观结构 (粉颗粒形态,蛋白质二次结构) 的演变.
主要成果:
- 较高的干燥温度加速了水分的蒸发,但增加了内部水分梯度,热应力和裂纹形成.
- 在中等干燥温度 (60°C-70°C) 观察到最佳的水分迁移和减少裂纹.
- 温度升高引发了玉米颗粒形态的显著变化,并改变了从α螺旋到随机线圈的蛋白质二级结构,增加了裂易感性.
结论:
- 热空气干燥温度通过湿度迁移和热应力显著影响玉米核的微观结构和裂纹形成.
- 建议使用中等干燥温度 (60°C-70°C),以优化干燥效率并最大限度地减少结构损坏.
- 该研究为优化玉米干燥过程以减少加工损失提供了分子级理论基础.
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