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…

Selective and sensitive quantification of wine biogenic amines using a dispersive solid-phase extraction clean-up/concentration method

Biogenic amines exist in numerous foods, including wine. They can have aliphatic (putrescine, cadaverine, spermine, and spermidine), aromatic (tyramine and phenylethylamine) and heterocyclic structure (histamine and tryptamine)

Valutazione dell’equilibrio vegeto-produttivo con metodiche di proximal sensing

Nel biennio 2008-2009, nell’ambito di un progetto multidisciplinare coordinato e finanziato dal Consorzio Tuscania, 4 vigneti in differenti zone della Toscana sono stati monitorati con strumenti di proximal sensing al fine di valutare la variabilità riscontrabile e ottenere delle indicazioni sulle risposte vegetative delle piante e quanti-qualitative delle produzioni.

Phototropic and geotropic shoot orientation: effect on physiological, vegetative and reproductive parameters

[English version below]

On a étudié l’effet de l’orientation des rameaux sur les paramètres physiologiques, végétatifs et reproductif durant deux saisons de croissance (2002/2003 et 2003/2004) dans la région de Stellenbosch dans une vignoble du cépage Merlot sur 99R conduite en espalier et taillé à cordon coursonné. Les vignes étaient espacées 2.7 x 1.5 m.

On the losses of dissolved CO2 during champagne aging

A misconception lingers in the minds of some wine consumers that Champagne wines don’t age. It’s largely a myth, certainly as far as the best cuvees are concerned. Actually, during the so-called autolysis period of time (in the closed bottle, after the “prise de mousse”), complex chemical reactions take place when the wine remains in contact with the dead yeast cells, which progressively bring complex and very much sought-after aromas to champagne. Nevertheless, despite their remarkable impermeability to liquid and air, caps or natural cork stoppers used to cork the bottles are not 100% hermetic with regard to gas transfers. Gas species therefore very slowly diffuse through the cap or cork stopper, along their respective inverse partial pressure. After the “prise de mousse”, because the partial pressure of CO2 in the bottleneck reaches up to 6 bars (at 12 °C), gaseous CO2 progressively diffuse from the bottle to the ambient air
(where the partial pressure of gaseous CO2 is only of order of 0,0004 bar).

Methodology to assess vine cultivation suitability using climatic ranges for key physiological processes: results for three South African regions

Le climat a de fortes implications sur le bon fonctionnement physiologique de la vigne et a besoin d’être quantifié afin de déterminer l’aptitude des régions à la culture de la vigne. Une méthode, qui pourrait éventuellement servir à prévoir l’aptitude des régions à la culture de la vigne, est proposée.