Terroir 2020 banner
IVES 9 IVES Conference Series 9 How a microscopic yeast makes a big difference – how geographic limitations of yeast populations can determine the regional aroma of wine

How a microscopic yeast makes a big difference – how geographic limitations of yeast populations can determine the regional aroma of wine

Abstract

Aim: Microbial biogeography contributes to regional distinctiveness of agricultural products and is important to determine for quality and marketing of wine products. We evaluated the microbial influence on wine characteristics by considering the microbial diversity of soil, plant, grapes, must and wine in grapegrowing regions across Victoria, Australia. 

Methods and Results: We sampled soils, plant parts, grapes, must and wine across vineyards in Victoria. We extracted DNA for microbial diversity profiling of fungi and bacteria and used gas chromatography- mass spectrometry to separate and identify small molecules in the headspace of wine. At a large scale (~400km), we found that vineyard ecosystems are structured and distinguished by fungal communities, and that fungal communities were the strongest contributor to the aroma of wine. Further studies considered a smaller scale of microbial diversity and investigated the changes in fungal community composition and diversity during the annual growth cycle of the grapevine. We found that fungal ecology is dependent on the grapevine habitat (roots, leaves, flowers/fruit) and developmental stage during the annual growth cycle. The influence of microbial biogeographic patterns decreased during wine fermentation as the fungal populations were dominated by Saccharomyces spp. yeasts. Further investigation of the strain diversity of Saccharomyces cerevisiae showed that this yeast can determine geographic patterns at a small scale and determines regional distinctiveness to influence wine characteristics within a single region. 

Conclusions:

Our results show that microbial distribution patterns seen in vineyards in Europe, North America and New Zealand are also observed in Australia, but the composition of yeasts may be distinct. The ability to define a region based on microbial diversity and fermentative yeasts may assist the industry in more closely defining sub-regions in Australia.

DOI:

Publication date: March 17, 2021

Issue: Terroir 2020

Type: Video

Authors

Di (Echo) Liu1, Pangzhen Zhang1, Qinglin Chen1, Jean-Luc Legras2, Deli Chen1, Kate Howell1*

1School of Agriculture and Food, University of Melbourne, Parkville 3010 Australia
2UMR SPO, INRAE, Montpellier France

Contact the author

Keywords

Fungal ecology, yeast, wine aroma 

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Assessment of the bottled storage conditions on the volatile composition and sensorial characteristics of white wines

The quality of bottled white wines is highly influenced by their storage conditions, mainly temperature, and exposure to light and oxygen (1, 2).

Characterization of non-cultivated wild grapevines in Extremadura (Spain) 

Several Eurasian wild grapevine populations were found along Extremadura region (southwestern Spain). For conservation and study, one individual from four different populations (named L1, L2, L5 and L6) was vegetatively propagated and planted at Instituto de Investigaciones Agrarias Finca La Orden (CICYTEX), Badajoz. The aim of the present work was to characterize those conserved individuals from four different populations based on both an ampelographic description and a molecular analysis. Three vines per individual were studied.

How to develop strategies of adaptation to climate change based on a foresight exercise?

Prospective studies raise a real intellectual interest for those who contribute to them or take cognizance of it. But they are often considered too difficult to operationalize

DNA-free editing to improve stress resilience of wine grape genotypes recalcitrant-to-regeneration

Wine viticulture, being firmly linked to the vine-terroir relationship, has always encountered significant bottlenecks to genetic innovation. Nonetheless, the development of new breeding strategies leading to the selection of stress resilient genotypes is urgent, especially in viticulture, where it would allow reducing the use of chemical treatments adopted to control fungal diseases. Genome editing represents an extremely promising breeding technique. Unfortunately, the well-known recalcitrance of several wine grape cultivars to in vitro regeneration strongly limits the exploitation of this approach, which to our knowledge has so far been developed on table grape genotypes with high regeneration potential.

AROMATIC AND FERMENTATIVE PERFORMANCES OF HANSENIASPORA VINEAE IN DIFFERENT SEQUENTIAL INOCULATION PROTOCOLS WITH SACCHAROMYCES CEREVISIAE FOR WHITE WINEMAKING

Hanseniaspora vineae (Hv) is a fermenting non-Saccharomyces yeast that compared to Saccharomyces cerevisiae (Sc) present some peculiar features on its metabolism that make it attractive for its use in wine production. Among them, it has been reported a faster yeast lysis and release of polysaccharides, as well as increased ß-glucosidase activity. Hv also produces distinctive aroma compounds, including elevated levels of fermentative compounds such as ß-phenylethyl acetate and norisoprenoids like safranal. However, it is known for its high nutritional requirements, resulting in prolonged and sluggish fermentations, even when complemented with Sc strain and nutrients.