terclim by ICS banner
IVES 9 IVES Conference Series 9 WINE FERMENTATION METABOLITES PRODUCED BY TWO TORULASPORA DELBRUECKII STRAINS ISOLATED FROM OKANAGAN VALLEY, BC, CANADA VINEYARDS

WINE FERMENTATION METABOLITES PRODUCED BY TWO TORULASPORA DELBRUECKII STRAINS ISOLATED FROM OKANAGAN VALLEY, BC, CANADA VINEYARDS

Abstract

Wine aroma is influenced by various factors, from agricultural practices in the vineyard to the enological choices made by winemakers throughout the vinification process. Spontaneous fermentations have a characteristically deeper complexity of aromas when compared to fermentations that have been inoculated with Saccharomyces (S.) cerevisiae because of the diversity of microflora naturally present on grape skins. Non-Saccharomyces yeast are being extensively studied for their ability to positively contribute to wine aroma and flavour. These yeasts are known to liberate more bound volatile compounds present in grape must than S. cerevisiae through the enzymatic action of β-glucosidases and β-lyases1. Torulaspora (T.) delbrueckii is known to stand out among these nonconventional yeasts by increasing the content of esters, terpenes and thiols in wine fermentations, together with low production of acetic acid, hydrogen sulfide and acetaldehyde.

In a previous study using Pinot Noir grapes from the Okanagan Valley (BC, Canada)2, a collection of non-Saccharomyces yeasts was isolated from late-stage spontaneous lab fermentations. These yeasts were screened for their fermentative performance based on residual sugar, ethanol concentration and production of non-volatiles such as glycerol and acetic acid in single fermentations using Chardonnay juice. From these, two strains of T. delbrueckii were selected for further analysis. The aim of the present work was to examine oenological traits such as ethanol, sulfite, and copper sulfate resistance for the two T. delbrueckii Okanagan Valley strains, the T. delbrueckii reference strain CBS1146, the commercial T. delbrueckii strain Zymaflore Alpha and a control S. cerevisiae strain. These five strains were also used to perform single yeast fermentations in Muscat juice. Non-volatile compounds were quantified by HPLC/RID and analyzed by ANOVA with no significant differences in residual sugars, ethanol and glycerol production, while CBS1146 displayed lower acetic acid than the other 4 strains. Volatiles such as terpenes, primary alcohols and esters were also semi-quantified by SPME-GC/MS, followed by Partial Least Squares-Discriminant Analysis. Differences were observed among the strains in aroma compounds including limonene, γ-terpinene, α-terpineol, ocimene, phenylethyl alcohol and 2-phenethyl acetate. This work will add to developing research on T. delbrueckii from the perspective of BC and Canadian wines.

 

  1. Belda, I., Ruiz, J., Alastruey-Izquierdo, A., Navascues, E., Marquina, D., & Santos, A. (2016). Unraveling the enzymatic basis of wine “flavorome”: A phylo-functional study of wine related yeast species. Frontier in Microbiology, 7, 1–13. DOI: 10.3389/fmicb.2016.00012
  2. Cheng, E., Martiniuk, J. T., Hamilton, J., McCarthy, G., Castellarin, S. D., & Measday, V. (2020). Characterization of Sub-Regional Variation in Saccharomyces Populations and Grape Phenolic Composition in Pinot Noir Vineyards of a Canadian Wine Region. Frontiers in genetics, 11, 908. DOI: 10.3389/fgene.2020.00908

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Joana Pico1, Elia Castellanos1, Simone D. Castellarin1, Vivien Measday1

  1. Wine Research Centre, University of British Columbia

Contact the author*

Keywords

Non-Saccharomyces yeast, Wine aroma, Fermentation metabolites, Volatile compounds

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

HOW OXYGEN CONSUMPTION INFLUENCES RED WINES VOLTAMMETRIC PROFILE

Phenolic compounds play a central role in sensory characteristics of wine, such as colour, mouthfeel, flavour and determine its shelf life. Furthermore, the major non-enzymatic wine oxidation process is due to the catalytic oxidation of phenols in quinones. Due their importance, during the years have been developed different analytical methods to monitor the concentration of phenols in wine, such as Folin-Ciocalteu method, spectrophotometric techniques and HPLC. These methods can also be used to follow some oxidation-related chemical transformations.
Read More

METHYL SALICYLATE: A TRENDY COMPOUND MARKER OF ZELEN, A UNIQUE SLOVENIAN VARIETY

The wine market interest for autochthonous varieties, particularly from less known wine regions, has significantly raised in the past few years. In that context, Slovenia, a small country from central Europe with a long winemaking tradition, is getting more and more attention, particularly through its range of unique regional varieties. Among them, Zelen, meaning “green” in Slovene, can only be found in the Vipava valley region, located on the western side of the country, near the border with Italy. When they are young, Zelen wines display very singular aromas reminiscent of rosemary, sage and white fruit. Despite its uniqueness, Zelen wine aromatic typicality is poorly documented in the literature.

Read More

Overhead spray water treatment as a mitigation strategy for reducing vine stress and preserving grape quality during heatwaves

Changes in climate have been influencing the quality of wine grapes worldwide. The impact of extreme climate events over short periods is increasingly recognized as a serious risk to grape quality and yield quantity. In this study the mitigation effects of a pulsed water spray on vine canopy during heatwave events has been evaluated for maintaining vine condition during the growing season and grape quality. Vines of three varieties (Malbec, Bonarda, and Syrah) under drip irrigation in the UNCuyo experimental vineyard were treated with an overhead pulsed water spray.

Read More

INVESTIGATION OF MALIC ACID METABOLIC PATHWAYS DURING ALCOHOLIC FERMENTATION USING GC-MS, LC-MS, AND NMR DERIVED 13C-LABELED DATA

Malic acid has a strong impact on wine pH and the contribution of fermenting yeasts to modulate its concentration has been intensively investigated in the past. Recent advances in yeast genetics have shed light on the unexpected property of some strains to produce large amounts of malic acid (“acidic strains”) while most of the wine starters consume it during the alcoholic fermentation. Being a key metabolite of the central carbohydrate metabolism, malic acid participates to TCA and glyoxylate cycles as well as neoglucogenesis. Although present at important concentrations in grape juice, the metabolic fate of malic acid has been poorly investigated.

Read More

THE ODORIFEROUS VOLATILE CHEMICALS BEHIND THE OXIDATIVE AROMA DEGRADATION OF SPANISH RED WINES

It is a well-established fact that premature oxidation is noxious for wine aromatic quality and longevity. Although some oxidation-related aroma molecules have been previously identified, there are not works carrying out systematic research about the changes in the profiles of odour-active volatiles during wine oxidation.

Read More