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…

Antimicrobial activity of oenological polyphenols against Gram positive and Gram negative intestinal multidrug-resistant bacteria

Bacterial antibiotic resistance is a major current health problem. Polyphenols have demonstrated antibacterial activity, and in this work we studied the effect of oenological polyphenols on the growth of intestinal multidrug-resistant strains of human and animal origin. Two Enterococcus faecium strains, resistant to vancomycin and other antibiotics, and four Escherichia coli strains, resistant to ampicillin and other antibiotics, were included in this study. All strains showed multidrug resistant phenotypes and genotypes to at least two antibiotic families.

Vineyard yield estimation using image analysis: assessing bunch occlusions and its dependency on fruiting zone canopy features

Performing accurate vineyard yield estimation is of upmost importance as it provides important benefits to the whole vine and wine industry. Recently, image-analysis approaches have been explored to address this issue however this approach has as main challenge the bunch occlusion, mostly by vegetation but also by neighboring bunches. The present work aims at assessing the magnitude of bunch occlusion by neighboring bunches and to evaluate its dependency on a selection of vegetative and reproductive vine parameters assessed at fruiting zone. Forty vine segments (1 m) of two vineyard plots of the white cultivars ‘Alvarinho’ and ‘Arinto’ were assessed for vegetative and reproductive features at fruiting zone and imaged with a 2D camera.

Selecting green cover species in the under-trellis zone of Lower Austrian vineyards

The under-trellis zone of vineyards is a sensitive area through which vines cover a significant portion of their nutrient and water needs. Mechanical and chemical methods are applied to suppress competing and tall-growing weeds to ensure optimal vine growth conditions. In addition to higher operating costs and depending on the soil conditions, these practices might lead to a long-term reduction in soil fertility and biodiversity. The presented study aims to analyse the suitability and interspecies competition of a selected green cover mixture of five local herbaceous species as potential green cover mixture in the under-trellis area of Lower Austrian vineyards.

Effect of drought on grapevine wood fungal pathogen communities using a metatranscriptomics approach

Crops are facing increasing biotic and abiotic stress pressures due to global changes. However, trade-off mechanisms between these stresses and the underlying physiological processes are still poorly understood, especially in perennial crop species. To better understand these trade-offs, we studied the effect of drought on grapevine (Vitis vinifera) physiology and esca-related wood fungal communities. Esca is a vascular disease caused by a community of wood-infecting pathogenic fungi, and characterized by trunk necrosis, leaf scorch symptoms, yield losses, and mortality.

Typicality of Rioja wines: identification of sensory profiles for the three subregions of DOCa Rioja

Within the DOCa Rioja three main production areas are differentiated: Rioja Alta (RA), Rioja Alavesa (RAv) and Rioja Oriental (RO). They are three diverse territories with particular characteristics that are claimed to give rise to differentiated profiles. The present work aims at evaluating the sensory diversity of young commercial red wines in these three subregions. Therefore 30 young red wines (mainly Tempranillo and vintage 2021), ten from each subregion, were sensory described following a non-verbal free sorting task and a verbal free comment task by 32 well-established Rioja winemakers.