Antioxidant capacity, polyphenols and biogenic amines content for Italian Controlled Denomination of origin (DOC) red wines characterization.

In Italy, the production of wines with a Controlled Denomination of Origin (DOC) and Controlled and Guaranteed Origin (DOCG) has increased over the past 20 years of 91.4%, rising from 14.3% of the total wine produced in 1989, to the current 32.7%. To these production must be added the wines with Typical Geographic Indication (IGT), which currently account for about 27.3%, and that, therefore, lead wines qualified in reference to the origin to weigh about 60% on national wine production. Authenticity of foods and, in particular, of wine has been extensively investigated because wine is an easily adulterated product. The production of DOC wines is particularly affected by this phenomenon. The appreciated antioxidant capacity of red wine is mainly due to the presence of polyphenols that have also influence on colour, taste of fullness, body, bitterness and astringency. Wines are known also to contain many biogenic amines. Their amounts and compositions depend on the type of grapes and their degree of ripeness and the climate and soil of the viticultural area, as well as vinification techniques. For these peculiar characteristics the potential of phenolic compounds and biogenic amines analysis for the differentiation of wines by grape variety, age or geographical origin has been recently recognized. Object of this study were samples of Italian red wines of five DOC wine varieties, chosen to be representative of the whole Italian wine production. Eleven biogenic amines (tryptamine, methylamine, ethylamine, agmatine, phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine) were determined by RP-HPLC with fluorimetric detection, after derivatization with dansyl chloride. The chromatographic data were then combined with spectrophotometric determinations of antioxidant capacity and total polyphenols. The subsequent data matrix structure was explored by Multivariate analysis techniques. The compounds analyzed demonstrated to be good descriptors to differentiate among the different wine varieties.