terclim by ICS banner
IVES 9 IVES Conference Series 9 VOLATILE AND GLYCOSYLATED MARKERS OF SMOKE IMPACT: EVOLUTION IN BOTTLED WINE

VOLATILE AND GLYCOSYLATED MARKERS OF SMOKE IMPACT: EVOLUTION IN BOTTLED WINE

Abstract

Smoke impact in wines is caused by a wide range of volatile phenols found in wildfire smoke. These compounds are absorbed and accumulate in berries, where they may also become glycosylated. Both volatile and glycosylated forms eventually end up in wine where they can cause off-flavors. The impact on wine aroma is mainly attributed to volatile phenols, while in-mouth hydrolysis of glycosylated forms may be responsible for long-lasting “ashy” aftertastes (1).

In order to assess smoke impact, a selection of volatile and glycosylated phenols is proposed, mainly based on research from Australia (2, 3). It includes the volatile phenols guaiacol, 4-methylguaiacol, ortho-, meta- and para- cresol, phenol, syringol, and 4-methylsyringol, as well as their glycosylated forms guaiacol rutinoside, 4-methylguaiacol rutinoside, cresol rutinoside, phenol rutinoside, syringol gen-tiobioside, and 4-methylsyringol gentiobioside. The accurate and reproducible measurement of these compounds is now possible, due to the commercial availability of standards and isotopic analogues.

In this study, we investigated the stability of these markers in bottled wines from smoke-exposed grapes, during a two-year timeframe. Wines monitored were a Chenin Blanc and a Chardonnay (whites), a Grenache (rosé), two Cabernet Sauvignons, a Zinfandel and a Grenache (reds).

No significant increases in guaiacol were observed in the white and rosé wines. Slight increases (2-3 μg/L) were observed in red wines, with the exception of the Pinot Noir (9 μg/L). Non-significant to slight increases were observed for phenol, except in the Zinfandel (10 μg/L). Large increases were observed for syringol in red wines only, especially in Cabernet Sauvignons (up to 60 μg/L). No significant increases were observed for the other volatile phenols measured.

All measured glycosylated markers were stable, in all wines. Therefore, increases in volatile phenols, when they happened, were not explained by the hydrolysis of corresponding glycosylated forms measured.

The observed increases in guaiacol and syringol, as well as the stability of the glycosylated forms measured, are consistent with results from a previous study (4). The stability of glycosylated markers makes them relevant in identifying wines from smoke exposed grapes, possibly for many years after bottling. A limitation is that some smoke impacted wines might show normal or even non-detectable levels of these glycosylated markers.

 

1. Christine M. Mayr, Mango Parker, Gayle A. Baldock, Cory A. Black, Kevin H. Pardon, Patricia O. Williamson, Markus J. Herderich, and I. Leigh Francis.  2014. Determination of the Importance of In-Mouth Release of Volatile Phenol Glycoconjugates to the Flavor of Smoke-Tainted Wines. Journal of Agricultural and Food Chemistry  62 (11), 2327-2336
2. Hayasaka, Y., Parker, M., Baldock, G.A., Pardon, K.H., Black, C.A., Jeffery, D.W. and Herderich, M.J. (2013) Assessing the impact of smoke exposure in grapes: development and validation of a HPLC-MS/MS method for the quantitative analysis of smoke derived phenolic glycosides in grapes and wine. Journal of Agricultural and Food Chemistry 61, 25–33.
3. Krstic, M.P., Johnson, D.L. and Herderich, M.J. (2015) Review of smoke taint in wine: smoke-derived volatile phenols and their glycosidic metabolites in grapes and vines as biomarkers for smoke exposure and their role in the sensory perception of smoke taint. Australian Journal of Grape and Wine Research 21, 537–553.
4. Renata Ristic R., Lieke van der Hulst L., Dimitra L. Capone, and Kerry L. Wilkinson. Impact of Bottle Aging on Smoke-Tainted Wines from Different Grape Cultivars. 2017.
5. Journal of Agricultural and Food Chemistry 65 (20), 4146-4152

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Eric Hervé¹, Darren Gullick¹ , Azeem Hasan¹, Anindya Pradhan¹, Gordon Burns¹

1. ETS Laboratories, 899 Adams St. Suite A, St. Helena, CA 94574, USA

Contact the author*

Keywords

smoke impact, volatile phenols, glycosylated phenols

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

SHIRAZ FLAVONOID EXTRACTABILITY IMPACTED BY HIGH AND EXTREME HIGH TEMPERATURES

Climate change is leading to an increase in average temperature and in the severity and occurrence of heatwaves, and is already disrupting grapevine phenology. In Australia, with the evolution of the weather of grape growing regions that are already warm and hot, berry composition including flavonoids, for which biosynthesis depends on bunch microclimate, are expected to be impacted [1]. These compounds, such as anthocyanins and tannins, contribute substantially to grape and wine quality. The goal of this research was to determine how flavonoid extraction is impacted when bunches are exposed to high (>35 °C) and extreme high (>45 °C) temperatures during berry development and maturity.

Read More

EXPLORING THE METABOLIC AND PHENOTYPIC DIVERSITY OF INDIGENOUS YEASTS ISOLATED FROM GREEK WINE

Climate change leads to even more hostile and stressful for the wine microorganism conditions and consequently issues with fermentation rate progression and off-character formation are frequently observed. The objective of the current research was to classify a great collection of yeast isolates from Greek wines based on their technological properties with oenological interest. Towards this direction, fourteen spontaneously fermented wines from different regions of Greece were collected for further yeast typing. The yeast isolates were subjected in molecular analyses and identification at species level.

Read More

A NEW STRATEGY AND METHODOLOGY FOR THE CHARACTERIZATION OF POLYPHENOLS IN FINING PRECIPITATE

Polyphenols are secondary metabolite widely distributed in plant kingdom such as in fruits, in grapes and in wine. During the winemaking process, polyphenols are extract from the skin and seed of the berries. Fining is an important winemaking step just before bottling which has an impact on wine stabilization and clarification. Most the time, fining agent are animal or vegetal protein while some of them can be synthetic polymer like PVPP or natural origin like bentonite.

Read More

REGULATION OF CENTRAL METABOLISM IN THE LEAVES OF A GRAPE VINES VA- RIETAL COLLECTION ON A TEMPERATURE CLINE

Grape (Vitis vinifera) is one of the world’s oldest agricultural fruit crops, grown for wine, table grape, raisin, and other products. One of the factors that can cause a reduction in the grape growing area is temperature rise due to climate change. Elevated temperature causes changes in grapevine phenology and fruit chemical composition. Previous studies showed that grape varieties respond differently to a temperature shift of 1.5°C; few varieties had difficulties in the fruit development or could not reach the desired Brix level.

Read More

ASSESSING THE ROLE OF 27 KNOWN BITTER COMPOUNDS IN COMMERCIAL WHITE WINES COMBINING LC-MS QUANTIFICATION AND SENSORY ANALYSIS

The balance between the different flavours of a wine largely determines its perception and appreciation by the consumers. In white wines, sweetness and sourness are usually the two poles balancing the taste properties. The bitter flavour, on the other hand, is frequently associated with a loss of equilibrium and all white wines (dry and sweet, young and aged) are affected.
Several bitter compounds are already well-described in wines.

Read More