IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 UHPLC-HRMS analysis for the evaluation of formation and degradation of polysulfides in wine 

UHPLC-HRMS analysis for the evaluation of formation and degradation of polysulfides in wine 

Abstract

The contribution of sulfur compounds to wine aroma has been studied for several years, as their role can be either positive, contributing to the fruitiness and typicity of some white wines like Sauvignon blanc, or negative when related to off-flavours caused by H2S. Recently, H2S formation from degradation of polysulfides has gained interest in the wine sector as it could potentially lead to wine defects or quality reduction (1). It has been proposed that polysulfides can be formed upon oxidation of thiol compounds (for example glutathione and cysteine) with Cu2+ or elemental sulfur and could form a reservoir for H2S release post-bottling (2,3,4). Polysulfide formation has been demonstrated in several matrices including real wines (5,6,7), but the exact reaction mechanisms have not been proven yet. It has been suggested that both chemical and biochemical activities can play a role (8), which is a topic that is still under investigation.
In the present work we investigated the possible technological factors that could influence the formation of polysulfides. Furthermore, we proposed a new method using both liquid chromatography with mass spectrometry and parallel ion chromatography in order to study the degradation of single polysulfides and the formation of H2S, respectively.

METHODS
For the study we used ultra-high-performance liquid chromatography (UHPLC) coupled to hybrid quadrupole/high-resolution mass spectrometry (HRMS, Q-Orbitrap) for the detection, characterisation and accumulation of polysulfides. For the study of polysulfide degradation UHPLC was used with an on-line fraction collector (UHPLC-FC) in order to isolate the single compounds. After collection the sampled compound was kept at 30°C to promote degradation and injections were performed until complete degradation. For the detection of H2S Ion Chromatography (IC) was used. For the technological studies, wines fortified with varietal thiols were treated with Cu2+ or Ag+ and subjected to accelerated aging and different musts were fermented with different oenological yeasts in single vinifications.

RESULTS
Using UHPLC-FC and subsequent UHPLC-HRMS it was possible to follow single polysulfide degradation in time. The technological studies revealed treatment effects of post-fermentation treatments with Cu2+ and Ag+ and significant differences were found in polysulfide profiles of wines fermented with different oenological yeasts. These studies gave new insides in the formation and degradation mechanisms of polysulfides, which is considered relevant with regard to potential alterations of wine quality

DOI:

Publication date: June 22, 2022

Issue: IVAS 2022

Type: Article

Authors

Dekker Susanne¹*, Nardin Tiziana¹, Fedrizzi Bruno², Van Leeuwen Katryna², Roman Tomas¹ and Larcher Roberto¹

¹FEM-IASMA Fondazione Edmund Mach, Via Edmund Mach, 1, 38098 San Michele All’adige TN
²School of Chemical Sciences, The University of Auckland, 23 Symonds Street, Auckland, 1142, New Zealand

Contact the author

Keywords

polysulfides, oxidation, UHPLC-HRMS, reductive odours

 

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.