In this study, a pocket-sized spectrometer and multivariate analysis were used for rapid authentication of coffee varieties (Arabica and Robusta) in three physical states (raw beans, roasted beans and powdered beans) to check mislabelling and fraud. Two main coffee varieties were collected from different locations in Africa, and the three physical states were scanned in the 740–1070 nm wavelength range. The spectral data were pre-treated with several derivative-based methods followed by chemometric analysis to build the prediction models for coffee beans (raw, roasted and powdered). The best results obtained for raw coffee beans was an accuracy of 0.92 and efficiency of 0.82; for roasted coffee beans, an accuracy of 0.92 and efficiency of 0.87; while for roasted powdered coffee, an accuracy of 0.97 and efficiency of 0.97. The results reveal that for a more accurate differentiation of coffee beans, the roasted powder offers the best results.
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