Classification of red wines analysed by middle infrared spectroscopy of dry extract according to their geographical origin

Abstract

Mid-infrared transmission spectroscopy and classical analyses have been used to classify 165 wines of the same variety (Gamay), from three geographical origins (Gaillac, Beaujolais and Touraine). For spectroscopic analyses; the wines were dried on polyethylene membrane and infrared spectra were recorded by transmission between 800 cm^-1 and 1800 cm^-1. Classical analyses included pH, total acidity, total phenol, colour, sugars and major acids. The three groups of wines were classified by applying factorial discriminant analyses with cross validation. 97 p. cent of wines were correctly classified, based on the infrared data, versus 67 p. cent based on the classical analyses.