Macrowine 2021
IVES 9 IVES Conference Series 9 Wine yeast species show strong inter- and intra-specific variability in their sensitivity to uv-c radiation

Wine yeast species show strong inter- and intra-specific variability in their sensitivity to uv-c radiation

Abstract

While the trend in winemaking is toward reducing the inputs and especially sulphites, the development of While the trend in winemaking is toward reducing the inputs and especially sulphites, the development of innovative process to ensure microbial stabilization is a relevant topic for the industry. UV-C process is a non-thermal technique widely used for food preservation. In this study, we evaluated the relative sensitivity to UV-C of various wine related yeast species. A first approach was conducted using a drop-platted system. 147 strains distributed amongst fourteen yeast species related to wine environment were plated on Petri dishes (with 3 different drop densities) and exposed to six increasing UV-C doses. An important variability in UV-C response was observed at the interspecific level. Cellar resident species, which are mainly associated with wine spoilage, expressed higher sensitivity to UV-C than vineyard resident species. A focus on B. bruxellensis species with 104 screened strains highlighted an important effect of the UV-C, with intra-specific variation. The impact of this intra-specific variation of UV-C sensitivity on wine treatment efficiency was then studied. Six B. bruxellensis strains(including two sulphites resistant strains) from three different genetic groups were separately inoculated in red wine Those inoculated wines were then treated in our home-made UV-C pilot which allows the continuous treatment of liquids at 200 L.h-1. 4968 J.L-1 were sufficient to achieve 4.70 and 5.17 log10 reduction for both sulphites resistant strains, resulting in populations lower than 1 CFU.mL-1 after UV-C treatment. 6624 J.L-1 were required to achieve the same level of population (<1CFU.mL-1) for 3 other strains. This treatment was not sufficient to achieve the same result only for one strain. These results highlight the potential of UV-C utilisation against wine yeast spoiler at cellar scale even in highly absorbent wine (α254 = 31.6 cm-1). They also show that intraspecific variability (in addition to the already known interspecific variability) may have an effect on the required doses for the microbiological stabilization of wines.

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Etienne Pilard

PhD student at ISVV,Jules HARROUARD PhD student at ISVV Warren ALBERTIN assistant professor at ISVV Cécile MIOT-SERTIER technician at ISVV Remy GHIDOSSI professor at ISVV

Contact the author

Keywords

UV-C treatment ; Wine shelf-life ; Brettanomyces bruxellensis

Citation

Related articles…

Volatile organic compounds: a role in elicitor-induced resistance of grapevine against pathogens?

As Vitis vinifera varieties are susceptible to fungal diseases, numerous chemical treatments are generally required to ensure the quantity and quality of the harvest. However, in the context of sustainable viticulture, there are increasing societal request, political incitation, and winegrowers’ awareness to reduce the use of pesticides.

Toasted Vine-Shoots As An Alternative Enological Tool. Impact On The Sensory Profile Of Tempranillo Wines

The use of toasted vine-shoots as an alternative enological tool to make differentiated wines has generated interest among researchers and wineries. However, the evolution of these wines in bottle and the effect on the sensory profile has not been studied so far.

Effect of one-year cover crop and arbuscular mycorrhiza inocululation in the microbial soil community of a vineyard

The microbial composition of the soil is an important factor to consider in viticulture, since its influence on the “terroir” and on the organoleptic properties of the wine have been demonstrated. Different agronomic techniques have the potential to modify the composition and functionality of the soil microbial community. Maintaining green covers is known to increase soil microbial diversity. The direct application of inoculum of beneficial microorganisms to the soil has also been used to increase their abundance. However, the environmental conditions of each site seem to have a determining weight in the result of these practices. In this study, we compared the effect on the microbial community of a cover crop with legumes in autumn and the inoculation of grapevines with commercial inoculum bases on Rhizophagus irregularis and Funeliformis mosseae in the previous spring. The study has been carried out in a vineyard in Binissalem, Mallorca, Spain. After applying the treatments, we will analyze the soil microbial communities using the data obtained from Illumina amplification of soil DNA from the 16S and ITS regions to analyze bacteria and fungi community, respectively. In addition, we will record the physicochemical characteristics of the soil at each sampling point. The result showed that agronomic management, in the short term, has less influence than soil characteristics on the composition of the soil microbiome. With these results, we can conclude that in a vineyard, agricultural techniques should focus on improving the characteristics of the soil to improve the biodiversity of the soil microbiota.

Different soil types and relief influence the quality of Merlot grapes in a relatively small area in the Vipava Valley (Slovenia) in relation to the vine water status

Besides location and microclimatic conditions, soil plays an important role in the quality of grapes and wine. Soil properties influence…

Plastid genomics of Vitis vinifera L. for understanding the molecular basis of  grapevine (Vitis vinifera L.) domestication

The precise molecular mechanisms underlying the domestication of grapevine (Vitis vinifera L.) Are still not fully understood. In the recent years, next-generation sequencing (NGS) of plastid genomes has emerged as a powerful and increasingly effective tool for plant phylogenetics and evolution. To uncover the biological profile of the grapevine domestication process comprehensively, an investigation should encompass both the cultivated varieties (V. vinifera subsp. Vinifera) and their wild ancestors V. vinifera subsp. Sylvestris) across all potential sites of their distribution and domestication.