Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences, Wanning 571533, China.
College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
Molecules. 2018 May 11;23(5):1146. doi: 10.3390/molecules23051146.
The aim of this study is to investigate the effect of microwave vacuum drying (MVD) on the drying characteristics and quality attributes of green coffee beans. We specifically focused on the effective moisture diffusion coefficient (), surface temperature, glass transition temperature (), water state, and microstructure. The kinetics of color changes during drying, total phenolic content (TPC), and antioxidant activity (DPPH, FRAP, and ABTS) were also characterized. Microwave power during MVD affected the porosity of coffee beans, their color, TPC, and antioxidant activity. The Allometric 1 model was the most suitable for simulating surface temperature rise kinetics. Thermal processing of green coffee beans resulted in increased , , Δ, and TPC values, and greater antioxidant capacity. These findings may provide a theoretical reference for the technical improvement, mechanisms of flavor compound formation, and quality control of dried green coffee beans.
本研究旨在探讨微波真空干燥（MVD）对绿咖啡豆干燥特性和品质属性的影响。我们特别关注有效水分扩散系数（）、表面温度、玻璃化转变温度（）、水状态和微观结构。还对干燥过程中的颜色变化动力学、总酚含量（TPC）和抗氧化活性（DPPH、FRAP 和 ABTS）进行了表征。MVD 过程中的微波功率会影响咖啡豆的孔隙率、颜色、TPC 和抗氧化活性。仿射 1 模型最适合模拟表面温度上升动力学。对绿咖啡豆进行热加工会导致升高、、Δ和 TPC 值，以及增强抗氧化能力。这些发现可能为技术改进、风味化合物形成机制以及干燥绿咖啡豆的质量控制提供理论参考。
