Terroir 2020 banner
IVES 9 IVES Conference Series 9 Comparing the chemical and sensory consequences of grapevine smoke exposure in grapes and wine from different cultivars and different wine regions in Australia

Comparing the chemical and sensory consequences of grapevine smoke exposure in grapes and wine from different cultivars and different wine regions in Australia

Abstract

Aim: This study aimed to benchmark the chemical and sensory consequences of grapevine exposure to smoke, by comparing: (i) the concentration of volatile phenols and volatile phenol glycosides in control and smoke-affected grapes from different cultivars and different wine regions; and (ii) the chemical and sensory profiles of wines made from control and smoke-affected grapes, from different cultivars.  

Methods and Results: Control and smoke-affected grapes and wines were sourced from a combination of: experimental trials (involving the application of smoke to different grapevine cultivars); and commercial vineyards located in Australian wine regions, some of which were exposed to bushfire smoke during the 2019/20 growing season. The concentrations of smoke taint marker compounds were determined in grapes and wine by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry; while wine sensory profiles were determined by descriptive analysis. 

Conclusions: 

Volatile phenols and volatile phenol glycosides remain useful chemical markers of smoke taint. Volatile phenol concentrations (in free and glycosylated forms) varied by cultivar and wine region, which likely reflects varietal differences in the naturally occurring (‘background’) levels of volatile phenols, and the density and duration of smoke exposure experienced in different regions.  

Significance and Impact of the Study: Research findings provide an initial benchmark of the ‘background’ levels of free and glycosylated volatile phenols that can occur naturally in grapes from different cultivars, as well as the concentrations of smoke taint marker compounds present in smoke-affected grapes and wine. These results can be used by industry to inform decisions around harvesting vs. rejecting smoke-affected grapes, albeit a greater understanding of baseline volatile phenol levels by cultivar and region is needed.

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type: Video

Authors

Kerry Wilkinson* and Renata Ristic 

School of Agriculture, Food and Wine, Waite Research Institute, The University of Adelaide, PMB 1, Glen Osmond, South Australia 5064, Australia 
ARC Training Centre for Innovative Wine Production, Waite Research Institute, PMB 1, Glen Osmond, South Australia 5064, Australia

Contact the author

Keywords

Cresol, guaiacol, smoke taint, syringol, volatile phenols, volatile phenol glycoconjugates

Tags

IVES Conference Series | Terroir 2020

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.