terclim by ICS banner
IVES 9 IVES Conference Series 9 EVALUATION OF INDIGENOUS CANADIAN YEAST STRAINS AS WINE STARTER CULTURES ON PILOT SCALE FERMENTATIONS

EVALUATION OF INDIGENOUS CANADIAN YEAST STRAINS AS WINE STARTER CULTURES ON PILOT SCALE FERMENTATIONS

Abstract

The interactions between geographical and biotic factors, along with the winemaking process, influence the composition and sensorial characteristics of wine¹. In addition to the primary end products of alcoholic fermentation, many secondary metabolites contribute to wine flavor and aroma and their production depends predominantly on the yeast strain carrying out the fermentation. Commercially available strains of S. cerevisiae help improve the reproducibility and predictability of wine quality. However, most commercial wine strains available on the market have been isolated from Europe, are genetically similar, and may not be the ideal strain to reflect the terroir of Canadian vineyards². Instead, indigenous S. cerevisiae strains may enhance the typical sensory properties and characteristic profile of the wine region³. The Okanagan Valley is the major wine-producing region in British Columbia, Canada. The Measday lab has isolated S. cerevisiae indigenous strains from Okanagan Valley vineyards that are genetically distinct from commercial strains⁴. After evaluating the oenological characteristics of six indigenous strains isolated from Okanagan Crush Pad (OCP) winery in laboratory-scale fermentations, two were selected for pilot-scale winery fermentations to assess their potential as wine starter cultures. Fermentations with OCP088 and OCP125 yeast strains were carried out in triplicate 250L stainless steel barrels at OCP winery. Vin Gris (VG, Pinot Noir) and Pinot Gris (PG) varietals were chosen, the grapes were pressed, and the juice was settled to remove skins before inoculation. Major metabolites (organic acids, sugars, and ethanol) were quantified using HPLC-RID, sugar in both wines was mainly fructose, ranging between 16 g/L and 20 g/L, ABV of the finished product ranged between 10.8 and 11.3 %. Volatile compounds (terpenes, esters, ketones, and higher alcohols) were identified using SPME-GC/MS We identified the following number of volatile compounds in each fermentation: OCP125 PG (56), OCP088 PG (52), OCP125 VG (45), OCP088 VG (44). The majority of volatile compounds were esters, which are known for their contribution to wine quality. OCP 125 tended to produce more terpenes than OCP 088. Some of these compounds are responsible for honey and grapefruit-like aromas, which are atypical of these varietals, adding to the complexity of the final product.

 

1. Welke, J. E., Zanus, M., Lazarotto, M., Schmitt, K. G., & Zini, C. A.. (2012) Volatile Characterization by Multivariate Optimization of Headspace-Solid Phase Microextraction and Sensorial Evaluation of Chardonnay Base Wines. Journal of the Brazilian Chemical Society, 23(J. Braz. Chem. Soc., 2012 23(4)). doi: 10.1590/S0103-50532012000400013
2. Borneman, Anthony & Forgan, Angus & Kolouchova, Radka & Fraser, James & Schmidt, Simon. (2016). Whole Genome Comparison Reveals High Levels of Inbreeding and Strain Redundancy Across the Spectrum of Commercial Wine Strains of Saccharomyces cerevisiae. G3 (Bethesda, Md.). 6. doi: 10.1534/g3.115.025692.
3. Nikolaou, E., Soufleros, E., Bouloumpasi, E., Tzanetakis N. (2006) Selection of indigenous Saccharomyces cerevisiae strains according to their oenological characteristics and vinification results. Food Microbiology 23, 205-211 doi:10.1016/j. fm.2005.03.004
4. Cheng, E., Martiniuk, J.T., Hamilton, J., McCarthy, M., Castellarin, S., and Measday, V. (2020). Characterization of Sub-Regional Variation in Saccharomyces Populations and Phenolic Composition in a Canadian Wine Region. Frontiers in Genetics 11, 1-19. doi: 10.3389/fgene.2020.00908.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Vivien Measday¹.

1. Wine Research Center, Faculty of Land and Food Systems, University of British Columbia, Canada

Contact the author*

Keywords

Indigenous strains, metabolites, volatile compounds, wine fermentation

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

EFFECTS OF INDUCED SUNBURN DAMAGES ON WHITE WINE PROPERTIES

Climate change is a great challenge for the environment and affects the wine industry as well. Sunburn damage of sensitive grapes increase with severe heat periods. Besides significant loss of yield sunburn, modifies sensory properties of the wines and may cause climate-related off-flavours. To initiate sunburn in a controlled way, in 2021 sunburn was directly induced in the vineyard with the GrapeBurner device, exposing grapes of the varieties Riesling and Pinot Blanc with UV and IR radiation. This device was first assembled by Kai Müller of the university in Geisenheim and consists of a carriage with 6 UV/IR lamps. A 15 min irradiation was applied in early September at 60°Oe. Due to the colder season in 2021 the grapes were not harmed by previous sunburn damage.

ANTIOXIDANT CAPACITY OF INACTIVATED NON-SACCHAROMYCES YEASTS

The importance of the non-Saccharomyces yeasts (NSY) in winemaking has been extensively reviewed in the past for their aromatic or bioprotective capacity while, recently their antioxidant/antiradical potential has emerged under winemaking conditions. In the literature the antioxidant potential of NSY was solely explored through their capacity to improve glutathione (GSH) content during alcoholic fermen- tation [1], while more and more studies pointed out the activity of the non-glutathione soluble fraction released by yeasts [2].

NEUROPROTECTIVE AND ANTI-INFLAMMATORY PROPERTIES OF HYDROXYTYROSOL: A PROMISING BIOACTIVE COMPONENT OF WINE

Hydroxytyrosol (HT) is a phenolic compound present in olives, virgin olive oil and wine. HT has attracted great scientific interest due to its biological activities which have been related with the ortho-dihydroxy conformation in the aromatic ring. In white and red wines, HT has been detected at concentrations ranging from 0.28 to 9.6 mg/L and its occurrence has been closely related with yeast metabolism of aromatic amino acids by Ehrlich pathway during alcoholic fermentation. One of the most promising properties of this compound is the neuroprotective activity against pathological mechanisms related with neurode-generative disorders including Alzheimer’s and Parkinson’s disease.

INOCULATION OF THE SELECTED METSCHNIKOWIA PULCHERRIMA MP1 AS A BIOPROTECTIVE ALTERNATIVE TO SULFITES TO PREVENT BROWNING OF WHITE GRAPE MUST

Enzymatic browning (BE) of must is caused by polyphenol oxidases (PPOs), tyrosinase and laccase. Both PPOs can oxidize diphenols such as hydroxycinnamic acids (HA) to quinones, which can later polymerize to form melanins [1], which are responsible of BE in white wines and of oxidasic haze in red wines. SO₂ is the main tool used to protect must from BE thanks to its capacity to inhibit PPOs [2]. However, the current trend in winemaking is to reduce and even eliminate this unfriendly additive. Among the different possible alternatives for protecting must against BE, the inoculation with a selected Metschnikowia pulcherrima MP1 is without any doubt one of the most promising ones.

EVALUATION OF INDIGENOUS SACCHAROMYCES CEREVISIAE ISOLATES FOR THEIR POTENTIAL USE AS FERMENTATION STARTERS IN ASSYRTIKO WINE

Assyrtiko is a rare ancient grape variety that constitutes one of the most popular in Greece. The objective of the current research was to evaluate indigenous Saccharomyces cerevisiae isolates as fermentation starters and also test the possible strain impact on volatile profile of Assyrtiko wine. 163 S. cerevisiae isolates, which were previously selected from spontaneous alcoholic fermentation, were identified at strain level by interdelta-PCR genomic fingerprinting. Yeasts strains were examined for their fermentative capacity in laboratory scale fermentation on pasteurized Assyrtiko grape must.