The conventional coffee roasting process includes roasting, grinding and extraction. Current study developed reversed coffee roasting process: grinding first before proceeding onto the roasting process. The physicochemical properties and volatile compound analysis were conducted on coffee prepared with conventional and reversed coffee roasting process. Two coffee samples, including coffee powder roasted with conventional process (C, control), and coffee powder prepared by reversed method of grinding and roasting (R. reversed). The L* value of commercial coffee was used as an index of roasting time and temperature. The particle size of R was significantly lower than that of C (p < 0.05) by 21.0%, respectively. The amount of trigonelline in C (264.23 μg/g) was significantly lower than R (p < 0.05). Other characteristics including L* value, moisture content, and pHs were not significant different between two coffee samples (p > 0.05). The volatile flavor compound profiles of two samples were slightly different, indicating potential flavor differences.

Industrial relevance

This study demonstrated new coffee roasting process, which is different from conventional coffee roasting process. Finding from current study suggest using the reversed coffee roasting process for commercial usage in coffee roasting process.

中文翻译：

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反向咖啡研磨和烘焙过程对理化性质（包括挥发性化合物分布）的影响

传统的咖啡烘焙过程包括烘焙，研磨和提取。当前的研究开发了反向咖啡烘焙过程：首先进行研磨，然后再进行烘焙过程。对采用常规和反向烘焙工艺制备的咖啡进行理化性质和挥发性化合物分析。两个咖啡样品，包括用常规方法烘焙的咖啡粉（C，对照）和通过反向研磨和烘焙方法制备的咖啡粉（R.反向）。商业咖啡的L *值用作烘烤时间和温度的指标。R的粒径分别比C的粒径低21.0％（p <0.05）。C中的藜芦碱含量（264.23μg/ g）显着低于R（p <0.05）。其他特性包括L *值，两种咖啡样品之间的水分含量和pH值无显着差异（p> 0.05）。两个样品的挥发性风味化合物特征略有不同，表明可能存在风味差异。

行业相关性

这项研究证明了新的咖啡烘焙过程，与传统的咖啡烘焙过程不同。从当前的研究中发现，建议将反向咖啡烘焙过程用于咖啡烘焙过程中的商业用途。