terclim by ICS banner
IVES 9 IVES Conference Series 9 Molecular approaches for understanding and modulating wine taste

Molecular approaches for understanding and modulating wine taste

Abstract

Wine consumers generally demand wines having a perception of softer tannins and less ripe, having a heaviness and richness on palate (full-body wine) with a limpid and stable color. However, polyphenol (tannins)-rich wines have been also correlated with unpleasant taste properties such as astringency and bitterness when perceived at high intensities. Modulating these unpleasant properties could be important for consumer’s approval of wines.
Indeed, polyphenols are usually associated with flavor, and particularly with astringency, due to their ability to complex with salivary proteins [1]. Saliva is rich in different SP families described to be involved in astringency, namely basic PRPs, glycosylated PRPs, acidic PRPs, statherin/P-B peptide and cystatins. However, due to saliva being a complex fluid, its protein profile may quantitatively and qualitatively vary under different conditions. Currently, astringency is recognized as a trigeminal sensation although the molecular pathway responsible for its onset is yet to be fully established. Moreover, it is unknown if the many different astringency mouthfeel sub-qualities such as velvet, puckering, harsh, among others, are perceived by different mechanisms. Besides the structural factors and medium conditions, there are some endogenous factors that affect astringency perception such as the physiological response, circadian rhythms, salivary flow rate and time of exposure. Indeed, astringency is perceived as a diffuse stimulus and dynamic process in the oral cavity that requires time to be elicited. It is known that astringency increases upon successive exposures to tannins [2,3].
Wine industry has some strategies to balance astringency and bitterness such as the use of some fining agents and also some winemaking practices (e.g. oak aging, batonnage and microoxygenations) leading to the loss of phenolics and also promoting the chemical change of some of them. While removing phenolic compounds is necessary to fulfill some organoleptic requirements of a beverage, the process must be controlled to avoid some collateral effects such as the loss of flavor [4]. Polysaccharides have been an emerging natural and sustainable option to be used on the modulation of taste properties. In fact, polysaccharides can influence salivary protein-tannin interactions and they could be used to modulate astringency and bitterness.

1. Soares, S., et al., Scientific Reports, 2020, 10, 12638.
2. Lesschaeve, I. and Noble, C. A., Am. J. Clin. Nutr, 2005, 81, 330S-5S.
3. Brand.o, E.; Soares, S.; Mateus, N.; de Freitas, V., J. Agri. Food Chem. 2014, 62, 9562−9568.
4. Francisco, T., et al., Food Res. Int., 2021, 143, 110261

DOI:

Publication date: February 11, 2024

Issue: OENO Macrowine 2023

Type: Article

Authors

Victor de Freitas

University of Porto, Faculty of Science, Portugal.
LAQV-REQUIMTE

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

ACIDIC AND DEMALIC SACCHAROMYCES CEREVISIAE STRAINS FOR MANAGING PROBLEMS OF ACIDITY DURING THE ALCOHOLIC FERMENTATION

In a recent study several genes controlling the acidification properties of the wine yeast Saccharomyces cerevisiae have been identified by a QTL approach [1]. Many of these genes showed allelic variations that affect the metabolism of malic acid and the pH homeostasis during the alcoholic fermentation. Such alleles have been used for driving genetic selection of new S. cerevisiae starters that may conversely acidify or deacidify the wine by producing or consuming large amount of malic acid [2]. This particular feature drastically modulates the final pH of wine with difference of 0.5 units between the two groups.

MONITOR SOME KEY PARAMETERS THROUGH THE IMPLEMENTATION OFCONTINUOUS CONTROL SYSTEMS OF THE MUST-WINE DURING MACERATION-FERMENTATION IN RED WINEMAKING TO MANAGE OPERATIONS IN “AUTOMATION”

This study is aimed to develop a complete tool for the winemaker with, complete and targeted “winemaking recipes” that can be adapted to criteria set by the winemaker, such as: grape variety, grape health status, degree of ripening, desired wine, redox status throughout the alcoholic fermentation.
To get such aim, specific sets of experiments using red grape juices from different varieties (Nebbiolo, Barbera, Pinot noir, etc.) collected at different technological and phenolic maturity points, will be held with “automatized 4.0 tanks” equipped with sensors for measuring: redox potential, dissolved oxygen, relative density, temperature, and color in order to collect a sufficient amount of data preparatory to the creation of operating models in the most widely winemaking situations in which the automatized 4.0 tanks “will be able to independently respond” with the right corrective actions (opening/closing aeration valve, execution/block pumping overs , etc.) if the key parameters exceed the limits of the recommended ranges set in the selected recipe.

PERCEPTUAL INTERACTIONS PHENOMENA INVOLVING VARIOUS VOLATILE COMPOUND FAMILIES LINKED TO SOME FRUITY NOTES IN BORDEAUX RED WINES

Fruity notes play a key role in the consumer’s appreciation of Bordeaux red wines. If literature provides a lot of knowledge about the nature of volatile compounds involved in this fruity expression, the sensory phenomena involving these compounds in mixture still need to be explored. Considering previous sensory works about the impact of esters and some overripening compounds, the goal of this work was to study the implication of perceptual interactions involving red wine odorant compounds of diverse origins and described as potentially affecting fruity aromatic expression.

AROMA ASSESSMENT OF COMMERCIAL SFORZATO DI VALTELLINA WINES BYINSTRUMENTAL AND SENSORY METHODOLOGIES

Sforzato di Valtellina DOCG is a special dry red wine produced from partially dehydrated Nebbiolo wine-grapes growing in the Rhaetian Alps valley of Valtellina (Lombardy, Italy). Valtellina terraced vineyards are located at an altitude of 350–800 m according to ‘heroic’ viticulture on steep slopes. The harvested grape bunches are naturally dehydrated indoors, where a slow and continuous withering occurs (about 20% w/w of weight loss), until at least 1st December when the grapes reach the desired sugar content and can be processed following a normal winemaking with maceration.

IN DEPTH CHARACTERIZATION OF OENOLOGICAL CHARACTERISTICS OF TWO LACHANCEA THERMOTOLERANS STARTER STRAINS

Non-Saccharomyces starter cultures became increasingly popular over the years because of their potential to produce more distinctive and unique wines. The major benefit of the use of Lachancea thermotolerans as a fermentation starter is its ability to produce relevant amounts of lactic acid and reduce alcoholic strength, making it valuable for mitigating negative impacts of climate change on grapes and wine quality. Besides, like any other non-Saccharomyces yeast, L. thermotolerans can significantly affect a whole range of other physico-chemical wine parameters.