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…

CHARACTERIZATION OF THE VOLATILE COMPOUNDS PROFILE OF COMMERCIAL GRAPPAS OBTAINED FROM THE POMACE OF AMARONE WINES

Grappa is a traditional Italian alcoholic beverage, with an alcohol content generally between 40-60% vol., obtained from the distillation of grape pomace used for the production of wine. Grappa are often aged in wooden barrels. There are various types of grappa: young, aromatic, aged, extra-aged depending on whether the distillate comes from aromatic vines or is aged in wooden barrels for shorter or longer periods. There is also flavored grappa if herbs, fruit or roots are added. All this makes it an extremely heterogeneous product both from an organoleptic and compositional point of view.

Beyond liking scores: the importance of the drinking experience to understand our consumers

The presentation will approach the understanding of wine consumers´ perception based on the experiential model suggested by Warell (2008). In this framework, wine consumption gives rise to a
variety of experiences related to the perception, understanding, and judgment of the product. These
multidimensional facets of the drinking experience can be explored by measuring affective, cognitive,
and sensory responses of consumers, which are shown to be stable regardless of the social context.

UNRAVELLING THE ROLE OF LACTIC ACID BACTERIA ON SPARKLING WINE ELABORATION THROUGH METABOLOMICS APPROACH

Xinomavro is a red grape variety from Northern Greece (Protected Designation of Origin), known for the nice acidities, perfectly appropriate for sparkling wine production (Rosé and Blanc de Noir). The elabo- ration of sparkling wine requires technical as well as scientific skills. Although the impact of the yeast strains and their metabolites on the final product quality is well documented, the action of bacteria still remains unknown.
The present work focuses (i) on the population diversity of lactic acid bacteria isolated from sparkling wines and (ii) on the technological effect of the species during sparkling wine elaboration.

THE FLAVANOL PROFILE OF SKIN, SEED, WINES, AND POMACE ARE CHARACTERISTIC OF EACH TYPOLOGY AND CONTRIBUTES TO UNDERSTAND THE FLAVAN- 3-OLS EXTRACTION DURING RED WINEMAKING

Wine flavanols are extracted from grape skin and seeds along red winemaking. Potentially, eight flavan-3-ol subunits may be present as monomers or as tannins constituents, being these catechin, epicathechin, gallocatechin, epigallocatechin end the gallates of the mentioned units. In this work the flavanol profiles of grape skins and seeds before (grapes) and after (pomace) red winemaking were studied together with the one in the corresponding wines. The trials were made over two vintages in Vitis vinifera cv. Tannat, Syrah and Marselan from Uruguay.

VOLTAMETRIC PROFILING OF RED WINE COMPOSITION DURING MACERATION: A STUDY ON FOUR GRAPE VARIETIES

During red wine vinification, maceration allows the must, and consequently the wine, to be enriched with several compounds that contribute to the creation of the typical organoleptic characteristics of red wines. Among these, extraction of polyphenols (PPs) during maceration is a major process of enological interest.
The purpose of this study was the evaluate the suitability of a rapid analytical approach based in linear sweep voltammetry to monitor PPs extraction during vinification.