terclim by ICS banner
IVES 9 IVES Conference Series 9 INSIGHTS ON THE ROLE OF GENES ON AROMA FORMATION OF WINES

INSIGHTS ON THE ROLE OF GENES ON AROMA FORMATION OF WINES

Abstract

Yeast secondary metabolism is a complex network of biochemical pathways and the genetic profile of the yeast carrying out the alcoholic fermentation is obviously important in the formation of the metabolites conferring specific odors to wine. The aim of the present research was to investigate the relative expression of genes involved in flavor compound production in eight different Saccharomyces cerevisiae strains.

Two commercial yeast strains Sc1 (S.cerevisiae x S.bayanus) and Sc2 (S.cerevisiae) and six indigenous S. cerevisiae strains (Sc3, Sc4, Sc5, Sc6, Sc7, Sc8) isolated during spontaneous fermentations were inoculated in Assyrtiko and Vidiano grape must. The fermentation kinetics, content of organic acids and gly- cerol production was monitored daily throughout the experiment. Transcript profiling of yeast genes in- volved in aroma formation and volatile composition of the must/wine was performed through real-time RT-PCR and SPE/GC–MS respectively, at four different time points of the fermentations. Specifically, a total of 28 volatile compounds were determined and the relative expression levels of 46 genes coding for acetyl-CoA synthetases, amino acid permeases, transaminases, reductases, decarboxylases, alcohol and aldehyde dehydrogenases, alcohol acetyltransferases, acyltransferases, esterases and glycosidases were recorded.

The relative expression levels of the genes implicated in amino acids, higher alcohols, ethyl esters, and terpenes metabolism, such as EEB1, EHT1, EXG1, ARO8, ARO9, PDC5, PDC6, ADH6, ADH3, AAD14, AAD16, were higher at the first three time points studied, since the most active period of aroma compound accumulation appears to occur in earlier fermentation stages. Additionally, the transcriptome data revealed substantial changes in expression patterns of genes between the different strains tested. In terms of the volatile characterization of the wines, the concentration levels of total esters and total alcohols appeared to be clearly distinct between the wines, which confirms that the production of volatile compounds is strain depended. Remarkable differences in the gene expression levels were observed when comparing the different strains which resulted in different aroma profiles.

This study enhances our understanding on yeast aroma metabolism-related gene expression and regulation. This knowledge can be a tool to modulate aroma production and orient the fermentation process towards a desirable wine aromatic profile.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Despina Lola¹, Chrysanthi Kalloniati², Emmanouil Flemetakis², Yorgos Kotseridis¹

1. Laboratory of Enology and Alcoholic Drinks, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
2. Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece

Contact the author*

Keywords

gene expression, Saccharomyces cerevisiae, yeast metabolism, volatile profile

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

THE EFFECT OF DIFFERENT TERROIRS ON AROMA COMPOUNDS OF ‘KALECIK KARASI’ WINES

Kalecik Karası is a domestic grape variety of Turkey, originating from Kalecik district, 80 km from Ankara. Although there is no definite evidence, it is known that it was used in wine production by many civilizations that lived in the Anatolian region, especially the Hittites. Compared to other black wine grapes, it stands out with its low tannin content, rich fruity aroma and complex structure. In good vintages, red fruits such as strawberries, cherries and raspberries stand out in the aroma profile. Although its structure is elegant, it has the potential to age and develop similar to the ‘Pinot Noir’ wine of the Burgundy region. This offers a complex aroma structure including red flowers, earth and ripe fruits.

IMPACT OF FINING WITH K-CARRAGEENAN, BENTONITE, AND CHITOSAN ON PROTEIN STABILITY AND MACROMOLECULAR COMPOUNDS OF ALBARIÑO WHITE WINE PRODUCED WITH AND WITHOUT PRE-FERMENTATIVE SKIN MACERATION

Pre-fermentative skin maceration is a technique used in white wine production to enhance varietal aroma, but it can increase protein concentration, leading to protein instability and haze formation [1]. To prevent protein instability, wine producers typically use fining agents such as bentonite, before wine bottling, which can negatively impact sensory characteristics and produce waste [2,3]. The aim of this study was to understand the impact of alternative techniques such as the application of polysaccharides (k-carrageenan and chitosan) on protein stability and on the wine macromolecular composition.

ANTI-TRANSPIRANT MODULATION OF GRAPE RIPENING: EFFECTS ON MERLOT VINE DEVELOPMENT AND ROSÉ WINE PHENOLIC AND AROMATIC PROFILES

Climate changes are impacting viticultural regions throughout the world with temperature increases being most prevalent.1 These changes will not only impact the regions capable of growing grapes, but also
the grapes that can be grown.2 As temperatures rise the growing degree days increase and with it the sugar accumulation within the berries and subsequent alcohol levels in wine. Consequently, viticultural
practices need to be examined to decrease the levels of sugars.

NEW TREATMENTS FOR TEMPRANILLO WINES BY USING CABERNET SAUVIGNON VINE-SHOOTS AND MICRO-OXYGENATION

Toasted vine-shoots as enological additive represents a promising topic due to their significant effect on wine profile. However, the use of this new enological tool with SEGs varieties different than wine and combined with others winemaking technologies, such as micro-oxygenation (MOX), has not been studied so far, despite this combination could result in wine with high chemical and organoleptic quality.

VOLATILE AND GLYCOSYLATED MARKERS OF SMOKE IMPACT: LEVELS AND PATTERNS OBSERVED IN 2020 WINES FROM THE UNITED STATES WEST COAST

Smoke impact in wines is caused by a wide range of volatile phenols found in wildfire smoke. These compounds are absorbed and accumulate in berries, where they may also become glycosylated. Both volatile and glycosylated forms eventually end up in wine where they can cause off-flavors, described as “smoky”, “bacon”, “campfire” and “ashtray”, often long-lasting and lingering on the palate. In cases of large wildfire events, economic losses for all wine industry actors can be devastating.