NEARINFRARED AND MIDINFRARED SPECTROSCOPIES IN FOOD AUTHENTICATION - COFFEE VARIETAL IDENTIFICATION

Near- and mid-infrared spectra of a set of 56 lyophilized coffee sampl es were collected. The sample set comprised 29 Arabica and 27 Robusta coffees and was prepared in the laboratory. Each spectral collection w as used separately to develop mathematical models for varietal authent ication of the coffees using factorial discriminant analysis and parti al least squares techniques. Subsequently, data from both spectral reg ions were combined and the chemometric approaches repeated. The relati ve success of the separate and combined approaches is discussed, as is the basis for the observed discriminations.