terclim by ICS banner
IVES 9 IVES Conference Series 9 PHENOTYPIC DIVERSITY AND BIO-PROTECTION CAPABILITY OF METSCHNIKOWIA SP. IN OENOLOGY

PHENOTYPIC DIVERSITY AND BIO-PROTECTION CAPABILITY OF METSCHNIKOWIA SP. IN OENOLOGY

Abstract

Nowadays, the trend is to reduce the use of chemical inputs in the food sector, including in oenology. One of the inputs widely used in the wine making process are sulfites, for its several properties: antimicrobial and antioxidiant. This use isn’t without consequences on consumer’s health and environment, it can lead for example to allergic reactions and pollution. To limit the addition of chemical inputs, microbial alternatives are used. It consists to inoculate in grape must, a micro-organism able to inhibit the growth of the negative indigenous flora during the phase before the fermentation and to guarantee the sensory qualities of wines. One of the specie the most used for its bio-protection capacity is the genus Metschnikowia. This project aims to study the phenotypical diversity in wine fermentative conditions and the diversity of bio-protector character of Metschnikowia sp.

To study the phenotypical diversity, 16 species of Metschnikowia within 50 strains have been selected depending their localization, their origins, and the species. These strains are used to ferment grape synthetical must, and the products of carbon central metabolism are analyzed by HPLC and the production of volatile molecules by GC-MS. In parallel, these strains are put in co-culture, with an acetic bacterium (Gluconobacter oxydans), known to lead to acetic souring, in commercial grape juice to study the interaction between yeast at 106cell/mL, and bacteria at 103cell/mL. Their growth is followed at day 0, 1, 2 and 7 through drop test on selective medium.

Similar to the fermentation aspects, the volatile profiles of the different strains were quite different, which corroborated the diversity of the Metschnikowia yeasts. The results of the drop test show an effect of bio-protection from the species Metschnikowia on the growth of G. oxydans. This work can underline both the potential of Metschnikowia yeast strains for inhibiting spoilage wine microorganisms and increasing aroma compounds.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

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

1. UMR SPO, Univ Montpellier, INRAE, Institut Agro, 34060 Montpellier, France
2. CIRM Levures, UMR SPO, Montpellier, France

Contact the author*

Keywords

wine fermentation, bioprotection, Metschnikowia, diversity

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

UNRAVELLING THE ROLE OF LACTIC ACID BACTERIA ON SPARKLING WINE ELABORATION THROUGH METABOLOMICS APPROACH

Xinomavro is a red grape variety from Northern Greece (Protected Designation of Origin), known for the nice acidities, perfectly appropriate for sparkling wine production (Rosé and Blanc de Noir). The elabo- ration of sparkling wine requires technical as well as scientific skills. Although the impact of the yeast strains and their metabolites on the final product quality is well documented, the action of bacteria still remains unknown.
The present work focuses (i) on the population diversity of lactic acid bacteria isolated from sparkling wines and (ii) on the technological effect of the species during sparkling wine elaboration.

INVESTIGATION OF FILM COATINGS AS A PROTECTIVE LAYER IN REDUCING THE ABSORPTION OF SMOKE PHENOLS INTO PINOT NOIR GRAPES

Wine grapes exposed to wildfire smoke have resulted in wines with burnt and ashy sensory characteristics¹, that are undesirable qualities in wine. In extreme wildfire events, this can lead to total loss of grape crop. Currently there are no effective solutions in the market to prevent the uptake of smoke compounds into grapes. In this study, previously developed innovative film coatings were tested to analyze their effectiveness in reducing smoke phenol absorption². Four different cellulose nanofiber-based film types were investigated.

A NEW TOOL TO QUANTIFY COMPOUNDS POTENTIALLY INVOLVED IN THE FRUITY AROMA OF RED WINES. DEVELOPMENT AND APPLICATION TO THE STU-DY OF THE FRUITY CHARACTER OF RED WINES MADE FROM VARIOUS GRAPE VARIETIES

A wide range of olfactory descriptors ranging from fresh and jammy fruit notes to cooked and oxidized fruit notes could describe the fruity aroma of red wines [1]. The fruity character of a wine is mainly related to the grape variety selected, to the terroir and the vinification process applied for its conception. In white wines, some volatile compounds confer directly their aroma to the wine while the question of “key” compound is more complex in red wines. According to many studies performed over the past decades, some fruity ethyl esters are directly involved in the fruity perception of red wines while others, present at subthreshold concentrations, participate indirectly to the fruity expression via perceptive interactions [2].

FUNGAL DIVERSITY AND DYNAMICS IN CHAMPAGNE VINEYARDS: FROM VINE TO WINE

Champagne is a well-known wine region in Northern France with distinct terroirs and three main grape varieties. As for any vineyard, wine quality is highly linked to the microbiological characteristics of the raw materials. However, Champagne grape microbiota, especially its fungal component, has yet to be fully characterized. Our study focused on describing this mycobiota, from vine to small scale model wine, for the two main Champagne grape varieties, Pinot Noir and Meunier, using complementary cultural and omics approaches.

Influence of agrophotovoltaic on vine and must in a cool climate

The current energy crisis means that interest in agrophotovoltaics has increased significantly. The reason behind this is that the system aims to combine agricultural production with energy production. During the three-year period from 2020 to 2022, the effects of photovoltaic panels on the vine, the yield and the quality of the must were studied in Walenstadt in northern Switzerland, an area with a cool, humid climate. 65 Pinot noir vines were planted in the 160m2 study area. Because of the large edge effects, only 3 repetitions with 4 vines each could be created. A significantly lower leaf infestation by Plasmopara viticola was observed among the panels in each of the three years.