terclim by ICS banner
IVES 9 IVES Conference Series 9 RED WINE AGING WITHOUT SO₂: WHAT IMPACT ON MICROBIAL COMMUNITY?

RED WINE AGING WITHOUT SO₂: WHAT IMPACT ON MICROBIAL COMMUNITY?

Abstract

Nowadays, the use of food preservatives is controversial, SO2 being no exception. Microbial communities have been particularly studied during the prefermentary and fermentation stages in a context of without added SO2. However, microbial risks associated with SO2 reduction or absence, particularly during the wine aging process, have so far been little studied.  The microbiological control of wine aging is a key issue for winemakers wishing to produce wines without added SO2. The aim of the present study is to evaluate the impact of different wine aging strategies according to the addition or not of SO2 on the microbiological population levels and diversity.

In 2021 and 2022, microbial community were monitored on merlot red wines during the wine aging process with different SO2 management and no SO2 addition. An experimental design (30L) was set up in triplicate and samples were collected from vatting to bottling to perform microbial analysis: population levels were monitored by plating on agar selective media for cultivable yeasts, acetic and lactic acid bacteria. From a subset of colonies obtained on solid medium, identifications at species level were made using the MALDI-TOF MS combining with a homemade database created by the laboratory.

In 2021, our results showed that without SO2, significant higher population levels of yeast and bacteria comparing with the sulphiting wines were present during the wine aging process. As expected, the higher species diversity was found at vatting. During the winemaking process, different species of lactic acid bacteria (10), acetic acid bacteria (3) and yeasts (8) were identified. Surprisingly, the effectiveness of SO2 addition at the end of MLF on the lactic acid bacteria showed contrasting results considering initial SO2 addition or not at vatting: population levels were significantly lower when SO2 was added only after malolactic fermentation. Our results regarding the impact of SO2 management during the winemaking process could provide opportunities for winemakers to reduce SO2 levels.  Furthermore, for the first time, microbial communities have been monitored throughout the winemaking process, in a reduced or without added SO2 context.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Sara Windholtz1,2, Julie Maupeu3, Amelie Vallet Courbin3, Marine Lucas3, Valerian Duarte4, Anne Hubert5, Stéphane Becquet5, Emmanuel Vinsonneau4, Isabelle Masneuf Pomarède1,2

  1. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d’Ornon, France
  2. Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France
  3. Microflora-ADERA, Univ. Bordeaux, INRAE, Bordeaux INP, Bordeaux Sciences Agro, UMR 1366 OENOLOGIE, ISVV, F33882 Villenave d’Ornon, France
  4. Institut Français de la Vigne et du Vin, Blanquefort, France
  5. Syndicat des Vignerons Bio Nouvelle-Aquitaine, Montagne, France

Contact the author*

Keywords

wine without SO₂, microbial communities, MALDI-TOF MS, malolactic fermentation

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

THE IMPACT OF NON-SACCHAROMYCES YEASTS ON THE WHITE WINE QUALITY

Selected strains of non-Saccharomyces yeasts showed a positive effect on sensory characteristics and aromatic complexity of wine. A sequential microbial culture of non-Saccharomyces and S. cerevisiae species is usually inoculated due to poorer fermentability of non-Saccharomyces species. The aim of the study was to investigate the role of non-Saccharomyces yeasts in the production of white wines. We evaluated how individual combinations of sequential inoculations of non-Saccharomyces and S. cerevisiae species affect the aromatic compounds (volatile thiols and esters) and sensory characteristics of the wines.

Read More

IDENTIFICATION AND LEVELS OF PHENOLIC COMPOUNDS (TANINS, ANTHO-CYANS) IN RED VARIETAL WINES (PROKUPAC AND BLACK TAMJANIKA) FROM SERBIA

The phenolic compounds of red wines represent a source of numerous benefits for human health, which is why they are a constant subject of scientific research. Winemaking in Serbia has a growing economic significance, with particularly autochthonous varieties included [1]. This research identifies and quantifies phenolic compounds of Serbian red varietal wines of Prokupac and Black Tamjanika varieties. Quantification of the level of phenolics has been conducted, including molecular tannins [(+)-catechin, (-)-epicatechin, procyanidin dimers B1, B2, B3, B4], molecular anthocyanins, and the mean degree of polymerization of tannins by HPLC by UV detection, total antioxidant capacity via spectrophotometric methods and chromatic characteristics via CIELAB.

Read More

UNRAVELING THE CHEMICAL MECHANISM OF MND FORMATION IN RED WINE DURING BOTTLE AGING : IDENTIFICATION OF A NEW GLUCOSYLATED HYDROXYKETONE PRO-PRECURSOR

During bottle aging, the development of wine aroma through low and gradual oxygen exposure is often positive in red wines, but can be unfavorable in many cases, resulting in a rapid loss of fresh, fruity flavors. Prematurely aged wines are marked by intense prune and fig aromatic nuances that dominate the desirable bouquet achieved through aging (Pons et al., 2013). This aromatic defect, in part, is caused by the presence of 3-methyl-2,4-nonanedione (MND). MND content was shown to be lower in nonoxidized red wines and higher in oxidized red wines, which systematically exceeds the odor detection threshold (62 ng/L).

Read More

METABOLIC INTERACTIONS OF SACCHAROMYCES CEREVISIAE COCULTURES: A WAY TO EXTEND THE AROMA DIVERSITY OF CHARDONNAY WINE

Yeast co-inoculations in winemaking have been investigated in various applications, but most often in the context of modulating the aromatic profiles of wines. Our study aimed to characterize S. cerevisiae interactions and their impact on wine by taking an integrative approach. Three cocultures and corresponding pure cultures of S. cerevisiae were characterized according to their fermentative capacities, the chemical composition and aromatic profile of the associated Chardonnay wines. The various strains studied within the cocultures showed different behaviors regarding their development.

Read More

UNCOVERING THE ROLE OF BERRY MATURITY STAGE AND GRAPE GENOTYPE ON WINE CHARACTERISTICS: INSIGHTS FROM CHEMICAL CHARACTERISTICS AND VOLATILE COMPOUNDS ANALYSIS

In a climate change context and aiming for sustainable, high-quality Bordeaux wine production, this project examines the impact of grape maturity levels in various cultivars chosen for their adaptability, genetic diversity, and potential to enhance wine quality. The study explores the effects on wine compo-sition and quality through sensory and molecular methods. We studied eight 14-year-old Vitis vinifera cv. grape varieties from the same area (VITADAPT plots 1 and 5): Cabernet Franc, Cabernet Sauvignon, Carmenère, Castets, Cot, Merlot, Petit Verdot, and Touriga Nacional.

Read More