微波辅助热空气干燥对干燥动力学,水迁移,介电性质和玉米微观结构的影响
Nan-Nan An1, Weihong Sun2, Dong Li1
1College of Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, National Energy R & D Center for Non-food Biomass, China Agricultural University, P.O. Box 50, 17 Qinghua Donglu, Beijing 100083, China.
Food chemistry
|June 2, 2024
概括
微波辅助热空气干燥 (MAHD) 与传统方法相比,可显著加快玉米干燥速度超过60%. 这种先进的干燥技术还通过保留颜色和营养素来提高玉米的质量.
科学领域:
- 农业工程 农业工程
- 食品科学与技术 食品科学与技术
- 干燥技术 干燥技术
背景情况:
- 传统的热空气干燥 (HAD) 对于玉米等农产品来说,耗费大量能源和时间.
- 优化干燥过程对于保持玉米质量和减少收获后损失至关重要.
- 了解干燥过程中的水迁移和微观结构变化是提高效率的关键.
研究的目的:
- 为了评估微波辅助热空气干燥 (MAHD) 对玉米的有效性.
- 在干燥动力学,水迁移和质量属性方面,将MAHD与传统热空气干燥 (HAD) 进行比较.
- 研究MAHD对玉米的介电性质,微观结构和整体质量的影响.
主要方法:
- 使用MAHD和HAD在各种微波功率 (1.2-3.6 kW) 和温度 (35-55 °C) 下进行玉米干燥实验.
- 使用两项模型分析干燥动力学.
- 低场核磁共振 (LF-NMR) 和磁共振成像 (MRI) 用于水迁移研究.
- 评估质量属性,包括颜色,胡卜素和脂肪酸度.
- 使用显微镜进行微结构分析,观察孔隙和裂.
主要成果:
- 与HAD相比,MAHD减少了30.95-64.29%的干燥时间.
- 在两种方法下,两项模型准确地描述了玉米干燥动力学.
- 在MAHD期间,LF-NMR/MRI表明玉米内的水分分布更加均.
- MAHD有效地保留了玉米的颜色和胡卜素,并降低了脂肪酸度.
- 在MAHD处理的玉米中观察到微度增加和裂,与干燥效率更高相关.
结论:
- 对于玉米来说,MAHD是一个比HAD更有效的干燥方法,大大减少了加工时间.
- MAHD通过保留颜色和胡卜素等关键属性并减少降解指标来提高玉米的质量.
- 用MAHD提高干燥效率与水迁移和玉米微观结构的变化有关,特别是孔隙性增加.
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