Classification of Coffee Beans by GC-C-IRMS, GC-MS, and ¹H-NMR

Figure 1

Box-plots for caffeine δ¹³C ratios obtained by GC-C-IRMS and for the 7 compounds quantified by GC-MS. The values and corresponding values were computed by ANOVA for each predictor. Although several predictors were found to be significantly different for both groups, the overlap observed between the distributions already suggested that the accuracy of the classifier would depend on the number of predictors included in the analysis.