Macrowine 2021
IVES 9 IVES Conference Series 9 Metabolomics comparison of non-Saccharomyces yeasts in Sauvignon blanc and Shiraz

Metabolomics comparison of non-Saccharomyces yeasts in Sauvignon blanc and Shiraz

Abstract

Saccharomyces cerevisiae (SC) is the main driver of alcoholic fermentation however, in wine, non-Saccharomyces species can have a powerful effect on aroma and flavor formation. This study aimed to compare untargeted volatile compound profiles from SPME-GC×GC-TOF-MS of Sauvignon blanc and Shiraz wine inoculated with six different non-Saccharomyces yeasts followed by SC. Torulaspora delbrueckii (TD), Lachancea thermotolerans (LT), Pichia kluyveri (PK) and Metschnikowia pulcherrima (MP) were commercial starter strains, while Candida zemplinina (CZ) and Kazachstania aerobia (KA), were isolated from wine grape environments. Each fermentation produced a distinct chemical profile that was unique for both grape musts. The SC-monoculture and CZ-SC sequential fermentations were the most distinctly different in the Sauvignon blanc while the LT-SC sequential fermentations were the most different from the control in the Shiraz fermentations. In the Sauvignon blanc fermentations SC-monoculture had the highest number of esters in the highest relative concentrations but all the yeasts had distinct ester profiles. CZ-SC displayed the highest number of terpenes in high concentrations but also produced a large amount of acetic acid. KA-SC was high in ethyl acetate. TD-SC had fewer esters but three distinctly higher thiol compounds. PK-SC had some off odor compounds while the MP had high levels of different methyl butyl-, methyl propyl-, and phenyethyl esters. LT-SC showed a relatively high number of increased acetate esters and certain terpenes. In the Shiraz fermentations on the other hand the LT-SC sequential fermentations were the most significantly different primarily in their ester, alcohol and terpene profiles as well as 1-ethyl-1H-pyrrole-2-carboxaldehyde, a pyrrole which has been described as having a burnt, roasted or smoky aroma. This compound was not found in any of the Sauvignon blanc fermentations. The other Shiraz non-Saccharomyces fermentations, with the exception of the LT-SC sequential fermentations, were distinct for their general lack of volatile compounds, a notable exception being terpenes. This differs significantly from the profiles seen in the Sauvignon blanc fermentations. Overall, this study gives a more detailed profile of these yeasts in two different grape musts and shows that non-Saccharomyces have great potential for increasing the complexity of both red and white wine volatile profiles.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Margaret Whitener*, Benoit Divol, Jan Stanstrup, Maret Du Toit, Urska Vrhovsek

*Fondazione Edmund Mach

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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