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…

EFFECTS OF HYDROXYTYROSOL ON THE CHEMICAL PROFILE AND SENSORY ATTRIBUTES OF A RED TUSCAN WINE

The chemical profile and sensory attributes were studied in Borrigiano IGT Toscana wine (Italy), a blend of Sangiovese 85% and Cabernet Sauvignon 15% grapes harvested in September 2020, where 2-(3,4-dihydroxyphenyl)ethanol (hydroxytyrosol, HT, [1]) was added to a 750-ml wine bottle in 3 different amounts (30, 60, 120 mg) and compared with the control (no HT addition). The study aimed to evaluate whether Polyphenol-HT1®, a high purity HT (>99%) produced by Nova Mentis using biotechnology, could be used as a supplement to sulfites and how it would impact the sensory and chemical profile of this wine [2]. Each sample was prepared in triplicate.

Read More

NEW INSIGHTS INTO THE FATE OF MARKERS INVOLVED IN FRESH MUSHROOM OFF-FLAVOURS DURING ALCOHOLIC FERMENTATION

The fresh mushroom off-flavour (FMOff) has been appearing in wines since the 2000s. Some C8 compounds such as 1-octen-3-one, 1-octen-3-ol, 1-hydroxyoctan-3-one, 3-octanol and others are involved in this specific off-flavour [1-3]. At the same time, glycosidic precursors of some FMOff compounds have been identified in musts contaminated by Crustomyces subabruptus [4], highlighting the role of aroma precursors in this specific taint. However, the fate of these volatile molecules and glycosidic fractions during fermentation is not well known.

Read More

MONOSACCHARIDE COMPOSITION AND POLYSACCHARIDE FAMILIES OF LYOPHILISED EXTRACTS OBTAINED FROM POMACES OF DIFFERENT WHITE GRAPE VARIETIES

The recovery of bioactive compounds from grape and wine by-products is currently an important and necessary objective for sustainability. Grape pomace is one of the main by-products and is a rich source of some bioactive compounds such as polyphenols, polysaccharides, fatty acids, minerals and seed oil. Polysaccharides contained in the grape cell wall can be rhamnogalacturonans type II (RG-II), polysaccharides rich in arabinose and galactose (PRAG), mannoproteins (MP), homogalacturonans (HG) and non pectic polysaccharides (NPP).

Read More

A NEW STRATEGY AND METHODOLOGY FOR THE CHARACTERIZATION OF POLYPHENOLS IN FINING PRECIPITATE

Polyphenols are secondary metabolite widely distributed in plant kingdom such as in fruits, in grapes and in wine. During the winemaking process, polyphenols are extract from the skin and seed of the berries. Fining is an important winemaking step just before bottling which has an impact on wine stabilization and clarification. Most the time, fining agent are animal or vegetal protein while some of them can be synthetic polymer like PVPP or natural origin like bentonite.

Read More

NEW INSIGHTS INTO THE EFFECT OF TORULASPORA DELBRUECKII/SACCHAROMYCES CEREVISIAE INOCULATION STRATEGY ON MALOLACTIC FERMENTATION PERFORMANCE

Winemaking is influenced by micro-organisms, which are largely responsible for the quality of the product. In this context, Non-Saccharomyces and Saccharomyces species are of great importance not only because it influences the development of alcoholic fermentation (AF) but also on the achievement of malolactic fermentation (MLF). Among these yeasts, Torulaspora delbrueckii allows in sequential inoculation with strains of S. cerevisiae shorter MLF realizations [5] . Little information is available on the temporal effect of the presence of T. delbrueckii on (i) the evolution of AF and (ii) the MLF performance.

Read More