Microbial diversity in grape musts from Austrian and South African grape varieties and regions

¹ Department of Viticulture and Oenology, Institute for Wine Biotechnology, Stellenbosch University, Stellenbosch, South Africa
² Höhere Bundeslehranstalt und Bundesamt für Wein- und Obstbau, Wienerstraße 74, 3400 Klosterneuburg, Austria
³ Department of Lithospheric Research, University Vienna, Althanstr. 14, 1090 Vienna, Austria
⁴ # further affiliation: Lehr- und Forschungszentrum Francisco Josephinum, Rottenhauserstraße 1, 3250 Wieselburg, Austria

Abstract

Vitis vinifera is one of the most widely planted crops and holds important economic value in South Africa and Austria. Grapes obtained from this plant harbour a complex fungal community which plays a crucial role in the wine fermentation process and influences wine flavour and aroma. For many years the contributions of the natural yeasts has been eclipsed by the use of active dry yeast (ADY) inoculant, mainly of the species Saccharomyces cerevisiae. However, recent studies show a growing interest in deciphering the natural microbial diversity and in promoting its persistence during fermentation in order to enhance wine typicity. The current preliminary study aims to provide a first broad assessment of the fungal community fingerprint of different grape varietals from different wine producing areas in Austria and South Africa through Automated Ribosomal Intergenic Spacer Analysis (ARISA). The ARISA profiles separated the samples according to country of origin, and suggested some regional and varietal separation within each country. Future work will evaluate the contribution of these fungal communities to wine chemical composition and sensorial distinctness.