Macrowine 2021
IVES 9 IVES Conference Series 9 Anthropogenic factors in modulations of fungal populations from grapes to wines and their repercussions on wine characteristics

Anthropogenic factors in modulations of fungal populations from grapes to wines and their repercussions on wine characteristics

Abstract

The effects of anthropogenic activities on vineyard (different plant protections) and in winery (pressing/clarification step, addition of sulfur dioxide) on fungal populations from grape to wine were studied. The studied anthropogenic activities modify the fungal diversity. Thus, lower biodiversity of grapes from organic modality was measured for the three vintages considered compared to biodiversity from ecophyto modality and conventional modality. The pressing / clarification steps strongly modify fungal populations and the influence of the winery flora is highlighted. The addition of SO2 changes the population dynamics and favors the dominance of the species S. cerevisiae. Moreover, use of SO2 had a particular impact on chemical wine composition with a slight increase in sulfurous compounds for the wines elaborated with sulfites, with an increase of the CHOS/CHO ratio of the mass numbers. However, the non-targeted chemical analysis shows also that these wines can still yet be distinguished at the end of the alcoholic fermentation (with or without SO2) depending on plant protection. Differences linked to plant protection mode are not totally masked by the use of SO2. Moreover, these differences are more visible after AF and can partly result from microbiological processes. Projecting the masses as filtered from the PLS–DA analysis on van Krevelen diagrams reveals specific chemical fingerprints for the organic, conventional and ecophyto wines. It is noteworthy that almost no CHOP- and CHONP-containing compounds are specific for a protection mode and that some CHONP-containing compounds are specific only for organic wines particularly. The organic wines appear to be characterized by CHONS-, CHONSP- and CHO-containing compounds located in particular in areas of amino acids and carbohydrates. The conventional wines appear to be specifically richer in sulfurous CHO-containing compounds with some located in the carbohydrate area and by CHONS- and CHOS-containing compounds. The ecophyto wines appear to be characterized by CHONS-, CHON- and CHO-containing compounds. These results show a significant influence of enological practices such as the use of sulfur dioxide on wine global chemical composition. However the effect of plant protection in the vineyard remains visible. For the first time, the existence of differences in the chemical signatures of wines associated with vineyard protection mode is highlighted.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Sandrine Rousseaux*, Cedric Grangeteau, Chloe Roullier-Gall, Hervé Alexandre, Michèle Guilloux-Benatier, Philippe Schmitt-Kopplin, Régis Gougeon

*University of Burgundy IUVV

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Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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