Unveiling the Impact of Infrared Drying on the Quality of Coffee Leaves: A Comprehensive Analysis of Physicochemical Indices, Antioxidant Potential, Maillard Reaction Products, and Aroma Profile

作者：Yuanyuan Huang, Yu Sun, Qingwei Cao, Dongyan Chen, Ronghai He, Xiumin Chen · 发表于：Journal of Food Science · 年份：2025 · DOI：10.1111/1750-3841.70400 · 被引用次数：8 · 研究领域：Tea Polyphenols and Effects、Phytochemicals and Antioxidant Activities、Morinda citrifolia extract uses

Coffee leaves, known for their health-promoting phytochemicals, have emerged as a potential functional tea ingredient. However, the effect of infrared drying (IFD) on its properties and sensory quality remains unexplored, limiting its industrial utilization. This study systematically elucidated the impact of IFD on drying kinetics, chemical compositions, Maillard reaction products (MRPs), flavor formation, and sensory characteristics of coffee leaves. IFD significantly reduced drying time by more than 50% and decreased protein loss by more than 5.79% compared to hot-air drying, while increasing total phenolic content (27.86% increase at 1300 W) and antioxidant activity (more than 50% increase). However, IFD resulted in higher levels of 5-hydroxymethylfurfural and α-dicarbonyl intermediates (glyoxal and methylglyoxal) compared to freeze-drying. Volatile analysis using HS-SPME-GC-MS revealed distinct aroma profiles: freeze-dried leaves showed a grassy aroma primarily characterized by hexanal, whereas IFD generated a more fruity-floral aroma with elevated levels of (E)-2-hexen-1-ol, octanal, and thermally derived pyrazine/pyridine. Key flavor markers such as 2,3-pentanedione and 6-methyl-5-hepten-2-one were uniquely elevated in IFD blades. The sensory evaluation confirmed that IFD-processed tea leaves received a score of 71.18 ± 3.04 and were characterized by a black tea-like flavor with caramel and fermented undertones. These findings suggest IFD as a time- and energy-efficient...