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…

Stomatal abundance in grapevine: developmental genes, genotypic variation, and physiology

Grapevine cultivation is threatened by the global warming, which combines high temperatures and reduced rainfall, impacting in wine quality and even plant survival. Breeding for varieties resilient to these challenges must address plant traits such as tolerance to supraoptimal temperatures and optimized water use efficiency while minimizing productivity and quality losses. Stomatal abundance (SA) determines the maximum leaf potential for transpiration and thus water loss and cooling. Since SA results from a developmental process during leaf emergence and growth, knowledge on the genetic control of this process would provide specific targets for modification.

Read More

Exploring the contributions of terroir factors on berry quality of cvs. Cabernet-Sauvignon and Merlot (Vitis vinifera L.) at the Eastern Foothills of the Helan Mountains region of China

Terroir leaves its mark on the accumulation of flavours in grape berries, triggering biochemical re-actions and ultimately shaping wine styles.

Read More

An automated cooling system to mitigate thermal and radiative stresses in Pignoletto white grapes

In the context of increasingly hot and dry summers, the adoption of innovative irrigation technologies has become essential for maintaining grape production while minimizing water use.

Read More

Using nanopore skim-sequencing to characterise regional epigenetic variability in New Zealand Sauvignon Blanc

Recent advancements in genomic sequencing technologies have enabled more detailed and direct studies of DNA methylation, which can help characterise epigenetic variations in plants. The Grapevine Improvement team at the Bragato Research Institute is studying the use of Oxford Nanopore sequencing to identify epigenetic changes associated with environmental differences among clonally-propagated grapevines.

This study involved sequencing DNA from the same Sauvignon Blanc clone, sourced from diverse New Zealand viticultural regions, using the PromethION platform.

Read More

Iso-/anisohydric behavior in wine grapes may be a matter of soil moisture

There are claims that wine grape cultivars are either isohydric or anisohydric; the former maintaining, and the latter decreasing, their plant water status as soil moisture declines. However, available information is inconsistent. There are those that show an existence of a continuum in cultivar response to soil moisture rather than a distinct categorization. Others even show both behaviors in the same cultivar grown in different environments. In this study we investigated the behavior of 30 own rooted Vitis vinifera cultivars during successive drydown and rewatering cycles over two growing seasons in arid eastern Washington (<200 mm annual precipitation).

Read More