terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Bioprotection of grape must by Metschnikowia sp.: genericity and mechanism

Bioprotection of grape must by Metschnikowia sp.: genericity and mechanism

Abstract

The market trend heads to food products with less chemical inputs, including in oenology. During the winemaking process, sulfites are commonly use to avoid microbiological contamination and stabilization of the wine thanks to its antimicrobial and antioxidant activities. Nevertheless, this use is not without consequences on human health and environment, leading for example to allergic reaction and pollution. A biological alternative to these sulfites has emerges: the bioprotection. This method consists to inoculate at the pre-fermentation stage, a microorganism able to inhibit the growth of the negative indigenous flora. The genus Metschnikowia is well know to have this bioprotection property, especially M. pulcherrima and M. fructicola, but the mechanisms remain poorly studied. This project aims to study the bioprotection abilities of 50 strains of Metschnikowia, including 16 species, against Gluconobacter oxydansand Brettanomyces bruxellensis, both known to lead to defects in organoleptic properties of the wine. To investigate the bioprotection effect, grape juice was inoculated with Metschnikowia sp. and G. oxydans or Metschnikowia sp. And B. bruxellensis. The capacity of Metschnikowia to inhibit G. oxydans growth was evaluated for 7 days by plate counting and by digital PCR for B. bruxellensis. In parallel, Metschnikowia species are inoculated in synthetic grape must to quantify the production of the acid pulcherriminic precursor. This acid is considered as a way for the yeast to compete for iron in the medium, and thus as a method of bioprotection. The results show a diversity in the bioprotection effect towards the spoilage microorganisms and in the production of the acid pulcherriminic precursor. The bioprotection could be an alternative in the sustainable pre-fermentative management of winemaking process.

Acknowledgements: We were grateful to Région Occitanie and INRAE MICA department for funding this project.

DOI:

Publication date: October 5, 2023

Issue: ICGWS 2023

Type: Article

Authors

Julie Aragno1, Angèle Thiriet2, Pascale Fernandez-Valle1, Cécile Grondin2, Jean-Luc Legras1,2, Carole Camarasa1, Audrey Bloem1

1 UMR SPO, Université Montpellier, INRAE, Institut Agro, Montpellier, France
2 CIRM Levures, UMR SPO, Montpellier

Contact the author*

Keywords

alcoholic fermentation, bioprotection, Metschnikowia sp., diversity

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Chemical profiling and sensory analysis of wines from resistant hybrid grape cultivars vs conventional wines

Recently, there has been a shift toward sustainable wine production, according to EU policy (F2F and Green Deal), to reduce pesticide usage, improve workplace health and safety, and prevent the impacts of climate change. These trends have gained the interest of consumers and winemakers. The cultivation of disease resistant hybrid grape cultivars (DRHGC), known as ‘PIWI’ grapes can help with these objectives [1]. This study aimed to profile white and red wines produced from DRHGC in South Tyrol (Italy). Wines produced from DRHGCs were compared with conventional wines produced by the same wineries. The measured parameters were residual sugars, organic acids, alcohol content, pigments and other phenolics by LC-QqQ/MS, colorimetric indexes (CIELab); and volatile profiles (HS-SPME-GCxGC-ToF/MS [2]).

Influence of irrigation frequency on berry phenolic composition of red grape varieties cultivated in four spanish wine-growing regions

The global warming phenomenon involves the frequency of extreme meteorological events accompanied by a change in rainfall distribution. Irrigation frequency (IF) affects the spatial and temporal soil water distribution but its effects on the phenolic composition of the grape have been scarcely studied. The aim of this work was to evaluate the effects of four deficit irrigation frequencies of 30 % ETo: one irrigation per day (T01), two irrigations per week (T03), one irrigation per week (T07) and one irrigation every two weeks (T15) on berry phenolic composition at harvest.

The colour pattern of flower arrangements influence wine tasters’ sensory description

The arrangements of flowers and wine counterparts are inextricably linked. Whether a fundamental aspect of tablescaping or acolytes to broader entertainment rituals, they have an entangled history since ancient times. The aim of this contribution is to verify the influence of visually delicate and robust flower arrangements on individual description of wines. Changes in the sensory description of wines were investigated during subjects’ (thirty-two participants) exposure to three different conditions: the presence of delicate, robust, or totally absent flower arrangements.

New oenological criteria for selecting strains of Lachancea thermotolerans for wine technology

The study conducted various fermentations of different grape juices using various strains of Lachancea thermotolerans and one strain of Saccharomyces cerevisiae. Because of the new conditions caused by climate change, wine acidity must be influenced as well as the volatile profile. Non-Saccharomyces yeasts such as L. thermotolerans are real options to mitigate the impact of climate change in wine production.

Crown procyanidin quantification in red wines, rosé wines and Port wines

Condensed grape tannins play a major role in the organoleptic properties and quality of red wine. Recently, a new sub-family of macrocyclic condensed tannins has been identified in red wine and named “crown tannins”. Indeed, the first compound of the family identified and characterised by NMR was the crown procyanidin tetramer which is composed of a macrocyclic structure composed of four (-)-epicatechins link together by B-type interflavanoid linkage in the following an alternative sequences of C4-C8 and C4-C6 linkage. The 3D structure of this unusual crown procyanidin family reveals a central cavity in the molecule [1].