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

Related articles…

Application of high power ultrasounds during red wine vinification

Wine color is one of the main organoleptic characteristics influencing its quality. It is of especial interest in red vinifications due to the economic resources that wineries have to invest for the extraction of the phenolic compounds responsible of wine color, compounds that are mainly located inside the skin cell vacuoles. Moreover, these phenolic compounds not only influence color but also other organoleptic properties such as body, mouthfeel, astringency and flavour. The transference of phenolic compounds from grapes to must during vinification is closely related with the type of grapes and the winemaking technique.

The commercial yeast strain as a significant source of variance for tyrosol and hydroxytyrosol in white wine

Tyrosol (TYR) and hydroxytyrosol (HYT) are bioactive phenols present in olive oil and wine, basic elements of the Mediterranean diet. TYR is reported in the literature for its interesting antioxidant, cardioprotective and anti-inflammatory properties. In wine, its concentration can reach values as high as about 40 mg/L
[Pour Nikfardjam et al. 2007] but, more frequently, this phenol – derived from yeast metabolism of tyrosine during fermentation – is present at lower levels, generally higher in red wines compared to whites. HYT was measured for the first time by Di Tommaso et al. [1998] in Italian wines – with maximum values of 4.20 mg/L and 1.92 mg/L for red and white wines, respectively – while definitely lower concentrations have been found later in Greek samples.

Colour assessment of port wines using colorimetric and spectrophotometric methods

Colour is an important quality parameter in wines and is the result of a complex mixture of pigments
(including anthocyanins and their derivatives, quinones, xanthyllium compounds, etc.). Red wine colour changes over time as pigments react between themselves and with other wine macromolecules
(particularly polyphenols). During wine tasting, colour is normally assessed on the outer rim of the wine profile in a tilted glass, since most wines are too opaque to be analysed in the middle of the glass. Therefore, depending on the depth of observation considered, the perception of wine colour can be different.

Dissecting the polysaccharide‐rich grape cell wall matrix during the red winemaking process, using high‐throughput and fractionation methods

Limited information is available on grape wall-derived polymeric structure/composition and how this changes during fermentation. Commercial winemaking operations use enzymes that target the polysaccharide-rich polymers of the cell walls of grape tissues to clarify musts and extract pigments during the fermentations. In this study we have assessed changes in polysaccharide composition/ turnover throughout the winemaking process by applying recently developed cell wall profiling approaches to both wine and pomace polysaccharides. The methods included gas chromatography for monosaccharide composition (GC-MS), infra-red (IR) spectroscopy and comprehensive microarray polymer profiling
(CoMPP) using cell wall probes.

Fractionation of copper and iron in wine: Assessment of potential macromolecule and sulfur binding agents

Copper and iron are known to substantially impact wine stability through oxidative, reductive or colloidal phenomena. However, the binding of metal ions to different wine components under wine conditions, and the impact of this binding on the ability of the metal ions to induce spoilage processes, is not well understood. This study surveyed a range of red and white wines for an understanding of the variability of broad metal categories within the wines. The techniques utilized included an electrochemical constant current stripping potentiometry technique (ccSP), and solid phase extraction (SPE) fractionation of wine with subsequent analysis of the metal content of each fraction by inductively coupled plasma – optical emission spectroscopy (ICP-OES).