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IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 The film-forming Pichia spp. in a winemaker’s toolbox: A simple isolation procedure and their performance in a mixed-culture fermentation of Vitis vinifera L. cv. Gewürztraminer must

The film-forming Pichia spp. in a winemaker’s toolbox: A simple isolation procedure and their performance in a mixed-culture fermentation of Vitis vinifera L. cv. Gewürztraminer must

Abstract

Certain yeast species belonging to the Pichia genus are known to form a distinctive film on grape must and wine. In a mixed-culture type fermentation, Pichia spp. (P. kluyveri in particular) are known to impart beneficial oenological attributes. In this study, we report on an easy isolation method of Pichia spp. from grape must by exploiting their film-forming capacity on media containing 10% ethanol. We isolated and identified two Pichia species, namely Pichia kudriavzevii and Pichia kluyveri, and subsequently co-inoculated them with Saccharomyces cerevisiae to ferment Gewürztraminer musts. Noteworthy differences included a significant increase in the 2-phenethyl acetate levels with the P. kluyveri co-fermentation and a general increase in ethyl esters with the P. kudriavzevii co-fermentation. Both Pichia co-inoculations yielded higher levels of glycerol in the final wines. Based on all the wine parameters we tested, the P. kluyveri strain that was isolated performed similarly to a commercial P. kluyveri strain.

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Scansani Stefano1, Van Wyk Niël1,2, Bou Nader Khalil1, Beisert Beata1, Brezina Silvia1, Fritsch Stefanie1, Semmler Heike1, Pasch Ludwig1, Pretorius Isak S.2, Von Wallbrunn Christian1, Schnell Sylvia3 and Rauhut Doris1

1Hochschule Geisenheim University
2Macquarie University
3Justus-Liebig-University

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Keywords

Phenethyl acetate, Pichia kluyveri, Pichia kudriavzevii, Non-Saccharomyces, Wine fermentation

Tags

IVAS 2022 | IVES Conference Series

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