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The hybrids are new varieties that are resistant to the cryptogamic diseases of vines, and they may be a good solution to the reduction of pesticide use. However, these new varieties have appeared recently and only few studies have been conducted to check the quality of the wine that they produce. In this study, wines originated from hybrids were chemically characterized (polyphenols, tannins, anthocyanins, and color analysis). Results show that their oenological parameters were close to those of the Vitis vinifera wines. The wines made from Vinifera (100%), with Vidoc, and all the resistant Bouquets studied are malvidin-3 glucoside dominant, and all the others hybrids varieties are cyanidin dominant. Furthermore, the hybrid wines had a higher concentration in condensed tannins and a lower one in molecular tannins compared with the Vitis vinifera wines, except for the Vidoc wines. As far as the anthocyanin content is concerned, the samples contained anthocyanin diglucosides, with the malvidin-3,5-diglucoside (malvin) the most abundant one. Also, their concentration in molecular anthocyanins were higher than the concentration in normal wines. The Vidoc wines do not contain any malvin. For the other wines, malvin co-eluted with cyanidin-3-O-glucoside and in this case, the cyanidin’s concentration was impressively higher than the Vidoc wines. The current OIV method gives different results for malvidol diglucoside compared to the use of an HPLC chromatography method (HPLC-DAD-QQQ). The current OIV method does not appear reliable in comparison with the HPLC method for detecting malvin. Finally, the hybrid wines had a darker blue/purplish color than the Vitis vinifera wines.

This communication actualizes the status of the research of the OIV working group on oenological tannins with the purpose of deepening the knowledge of the mechanisms and functionalities of oenological tannins in winemaking. The obtained results confirm that oenological tannins really exert an effect as copigments and that they really protect the wine color against the negative effect of the enzyme laccase present in grapes affected by the infection of Botrytis cinerea.

International audience; Grapes (Vitis spp.) are economically significant fruit species. Many scientific advances have been achieved in understanding physiological, biochemical, and molecular aspects of grape berry maturation. Some of these advances have led to the improvement of wine quality through better grape growing practices; but this avenue of research is still wide open due to the complexity of the biochemical mechanisms involved in the development and ripening of grapes and their response to environment. The Biochemistry of the Grape Berry is a pioneer offering for readers - giving a focused and integrated coverage of the key biochemical and molecular aspects of grape berry development and ripening. Readers will benefit from a comprehensive and updated coverage on key steps, mechanisms and regulation in grapevine biochemistry and molecular biology, provided by an international team of leading scientists. It provides useful references on this research area and original data from laboratories worldwide. The comprehensive range of topics covered in this e-book is valuable to a multidisciplinary readership including plant physiologists, enologists, microbiologists, wine makers, biochemists and students. Thus The Biochemistry of the Grape Berry represents a step forward in the comprehension of grape berry biochemistry, wine quality and health benefits.

Chapter 9; International audience; This chapter focuses on the health-promoting properties of different wine and table grape cultivars, The polyphenolic composition of grapes, i.e. flavonoids, flavonols, flavan-3-ols, anthocyanidins, phenolic acids, hydroxycinnamic acids and stilbenes, among others, and their medicinal properties are discussed and the effects of postharvest treatments on the bioavailability of these health-promoting compounds are highlighted.

A method based on graphite furnace atomic absorption spectrometry (GFAAS) was developed for determining platinum in wine. Wine samples were prepared by microwave acid digestion or dry mineralization. The method of standard addition was used for Pt determination in untreated wine samples and mineralized samples. Analyte modifiers and furnace conditions were optimized. Effects of cations (Mg2+, Ca2+, K+, Na+, and NH4+) and anions (PO4(3)-, SO4(2)-) were tested separately and in combination. Analytical characteristics of the method were optimized for analyte recovery and signal enhancement. Recoveries ranged from 92.5 to 102%, and precision reproducibility relative standard deviation varied from 7.5 to 10%. Red, rosé, and white wines from France were analyzed. Platinum levels found in most wines were very low (10 micrograms/L).

A method was developed for the speciation analysis of ionic organolead compounds in wine. The analytes were extracted as diethyldithiocarbamate complexes into hexane and propylated with a Grignard reagent. The derivatized extract was analyzed by capillary gas chromatography/microwave-induced-plasma atomic emission spectrometry. The method of standard additions was used for calibration to correct for variable recoveries and signal enhancements. Red, rosé, and white wines from southern France were analyzed. Trimethyllead was the ubiquitous species. The wines made from grapes grown close to industrial zones showed elevated concentrations of ethyllead species. The concentrations of methyllead and ethyllead found in wines were compared with the concentrations of organolead found in rain water and plant sap collected in the viticultural regions. The ratio of methyllead to ethyllead in wines greatly exceeded the same ratio found in atmospheric deposits.