In this research, the application of the first order derivative spectra was employed to determine the levels of caffeine (CAF) and chlorogenic acids (CGA) in defective (immature, black, and sour) and nondefective coffee beans without using extraction or background correction techniques. The extreme points of first order derivate spectra of these compounds were at the wavelength of 260 and 292 nm enable to quantify the contents of CAF and CGA, respectively. The level of CAF and CGA in coffee beans determined by this method is ranged from 1.2 ± 0.12–1.46 ± 0.47% and 4.04 ± 0.44–4.43 ± 0.43%, respectively. The study results also indicated total contents of CAF and CGA levels discriminate the defective and nondefective coffee beans with higher CAF and CGA contents being observed in defective coffee beans. As the method is extremely rapid, easy, and inexpensive and also requires minimal sample preparation for the quantification of CAF and CGA contents in coffee, it could be a valuable quality control technique.

中文翻译：

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一阶导数光谱用于确定有缺陷和无缺陷咖啡豆中的咖啡因和绿原酸

在这项研究中，使用一阶导数光谱的应用来确定有缺陷（未成熟，黑和酸）和无缺陷咖啡豆中咖啡因（CAF）和绿原酸（CGA）的水平，而无需使用提取或背景校正技术。这些化合物的一阶导数光谱的极点分别在260和292 nm的波长处，能够分别定量CAF和CGA的含量。用这种方法测定的咖啡豆中CAF和CGA的含量分别为1.2±0.12-1.46±0.47％和4.04±0.44-4.43±0.43％。研究结果还表明，CAF和CGA的总含量可以区分有缺陷和无缺陷的咖啡豆，在有缺陷的咖啡豆中可以观察到较高的CAF和CGA含量。由于该方法非常快速，简便，