This work presents the study of the fragrance and aroma of roasted coffee with the Coffee-NOSE prototype. The hardware system was developed with two chambers, one for the MOx gas sensor array, and the other for the concentrated coffee sample. A digital gas flow controller was integrated into the detection chamber for the sampling, detection and signal processing cycles. The threshold detection technique by conductance change was used in the gas sensor arrangement. The influence of the gas flow was controlled and separated from the interactions between the sample and the sensor array. The acquired data and signals were treated with the principal components method. The system allowed the detection of fragrance and aroma thresholds in three levels of light, medium and dark roast, suitable for the evaluation of coffee quality.