Macrowine 2021
IVES 9 IVES Conference Series 9 Management of varietal thiols in white and rosé wines using biotechnical tools

Management of varietal thiols in white and rosé wines using biotechnical tools

Abstract

The present study evaluates the effect of prefermentative maceration enzymes and yeast autolysate on the concentration of conjugated precursors and volatile thiols, respectively.Sauvignon blanc and Merlot grapes underwent skin-contact maceration with or without pectolytic enzymes, for the production of white and rosé wines. Significant differences in the extraction of 3- sulfanylhexan-1-ol (3-SH) precursors were observed in juices from Merlot grapes. The use of maceration enzymes led to an increase in both S-glutathionylated (GSH-3SH) and S-cysteinylated (Cys-3SH) precursors. The same trend of extraction was observed in Sauvignon blanc grapes, even if not statistically differentiated. In relation to 4-methyl-4-sulfanyl-pentan-2-one (4-MSP) precursors, the Cys-4MSP was the sole compound to be found, exclusively in Sauvignon blanc must. However, the enzyme treatment did not increase the concentration of this precursor. Grapes were pressed and racked after 24 hours of cold settling. For each variety, both musts were fermented in triplicate, in the presence and absence of a yeast autolysate. The nutrition management imparted significant differences between the volatile thiols in the final wines. The use of yeast autolysate increased the 3-SH content by ⁓25% and ⁓46%, in both Sauvignon blanc and Merlot wines, respectively. Moreover, the concentration of 4-MSP was four-fold higher in Sauvignon blanc wines supplemented with yeast nutrients. In Merlot wines 4-MSP was undetectable, result consistent with the absence of its precursors in the must of this variety.

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Adelaide Gallo¹, Alice Barbero¹, Loris Tonidandel¹, Rémi Schneider², Roberto Larcher¹, Tomas Roman¹

¹ Fondazione Edmund Mach—Technology Transfer Center, Via Edmund Mach 1, 38010 San Michele all’Adige, Italy
² Oenobrands SAS, Parc Agropolis II – Bât 5, 2196 Bd de la Lironde, CS 34603, CEDEX 05, 34397
Montpellier, France

Contact the author

Keywords

3- sulfanylhexan-1-ol; 4-methyl-4-sulfanyl-pentan-2-on; thiol precursors; maceration; wine aroma; pectolytic enzymes; yeast nutrients

Citation

Related articles…

Measurement of grape vine growth for model evaluation

Within a research project for simulating the nitrogen turnover in vineyard soils and the nitrogen uptake by the grape vine, a previously developed plant growth model (Nendel and Kersebaum 2004) had to be evaluated. A dataset was obtained from a monitoring experiment at three vineyard sites with different soil types, conducted in the years 2003 and 2004.

White wine light-strike fault: a comparison between flint and green bottles under the typical supermarket conditions

Consumer preference favors flint-glass wine bottles over the traditional dark-colored, but it is documented that light exposure can cause white wines to produce off-aromas and change in color, and consequently da[1]mage their quality. Aim of the study was to study the white wine shelf life under the typical supermarket conditions, by recording the light and temperature exposure, the colorimetric changes, and the light-strike fault. METHODS: One pilot experiment based on two white wines and eight-time points and one kinetic experiment based on four white wines and seven-time points were designed and realized using a typical supermarket shelf for 32 and 50 days, correspondently. By installing prototype sensors at 32 points of the shelf, the temperature, UV, IR, and Visible light exposure were registered every 10 min. Approximately 600 commercial wines, bottled in flint and colored glass, were used. The colorimetric changes of the wines were registered and the light-strike fault was evaluated.

Towards a better understanding of cultivar susceptibility to esca disease: results from a pluriannual common garden monitoring

Grapevine (Vitis vinifera L.) exhibits a high level of genetic and phenotypic diversity among the approximately 6000 cultivars recorded. This perennial crop is highly vulnerable to numerous fungal diseases, including esca, which is a complex vascular pathology that poses a significant threat to the wine sector, as there is currently no cost-efficient curative method[1]. In this context, an effective approach to mitigate the impact of such diseases is by leveraging the crop’s genetic diversity. Indeed, susceptibility to esca disease appears to vary between cultivars, under artificial or natural infection. However, the mechanisms and varietal characteristics underlying cultivar susceptibility to esca are still unknown.

Grapevine downy mildew development as affected by chitosan spray treatments and metabolomics implications

Chitosan has been shown to enhance grapevine tolerance toward downy mildew while reducing the environmental impact of traditional protection products.

Survey of phenological stages of disease-resistant varieties in Friuli Venezia Giulia region

Context and purpose of the study. The primary fungal diseases affecting grapevines in Europe are downy mildew and powdery mildew.