In the last few years the development of HPLC techniques together with multivariate statistical methods allowed to set methodics of large discriminant and classing efficacy in the study of wine-grapes.
The phenolic compounds (cynnamic acids and anthocyanidins) in thirty different wines grown in 4 different zones of Tuscany (Arezzo, Grosseto, Pisa and Lucca) have been analyzed by HPLC.
The analytical data were statistical worked out by two analysis ACP and a linear discriminant analisys in order to discriminate the four zones, using Fisher linear function.
The stepwise technique, to choose variables, pointed out the delphinidin-g, the peonidin-g, the ratio of three/two-sostituited anthocyanines, the sum of cis and trans-cutaric acids, the caffeic acid and the ratio of caffeic acid and the sum of cutaric acids among the most important.
Then we worked out 6 comparisons between two zones and exactly AR/LU, AR/PI, AR/GR, LU/PI, LU/GR and PI/GR.
The environment discriminant threshold, the differences, the discriminant functions of vine-variety in every zone and the measure of discrimination errors were obtained.
Therefore a vinevariety-environment interaction is quite probable.
Authors: A.Piracci, P.Storchi, P.Bucelli, F. Giannetti, V. Faviere
Istituto Sperimentale per l’Enologia Via di Vertine 1 53013 Gaiole in Chianti (SI)
Istituto Sperimentale per la Viticoltura – Arezzo
Email: piracci@inwind.it