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…

EFFECT OF MICRO-OXYGENATION IN COLOR OF WINES MADE WITH TOASTED VINE-SHOOTS

The use of toasted vine-shoots (SEGs) as an enological tool is a new practice that seeks to improve wines, differentiating them and encouraging sustainable wine production. The micro-oxygenation (MOX) technique is normally combined with alternative oak products with the aim to simulate the oxygen transmission rate that takes place during the traditional barrel aging. Such new use for SEGs implies a reduction in color due to the absorption by the wood of the responsible compounds, therefore, given the known effect that MOX has shown to have on the modification of wine color, its use together with the SEGs could result in an interesting implementation with the aim to obtain final wines with more stable color over time.

SENSORY EVALUATION OF WINE AROMA: SHOULD COLOR-DRIVEN DESCRIPTORS BE USED?

The vocabulary used to describe wine aroma is commonly organized according to color, raising the question of whether they reflect the reality of olfactory perception. Previous studies have assumed this convention of color-aroma matching, and have investigated color’s influence on the perception of aroma only in dyed white wine or in red wine from particular places of origin. Here 48 white and red varietal wines from around the world were evaluated in black glasses then in clear glasses by a panel of wine experts, who gave intensity ratings for aroma attributes commonly used by wine professionals. In black glasses, aromas conventionally associated with white wine were perceived in the red wines, and vice versa.

VOLATILE AND GLYCOSYLATED MARKERS OF SMOKE IMPACT: LEVELS AND PATTERNS OBSERVED IN 2020 WINES FROM THE UNITED STATES WEST COAST

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, described as “smoky”, “bacon”, “campfire” and “ashtray”, often long-lasting and lingering on the palate. In cases of large wildfire events, economic losses for all wine industry actors can be devastating.

THE EFFECT OF DIFFERENT TERROIRS ON AROMA COMPOUNDS OF ‘KALECIK KARASI’ WINES

Kalecik Karası is a domestic grape variety of Turkey, originating from Kalecik district, 80 km from Ankara. Although there is no definite evidence, it is known that it was used in wine production by many civilizations that lived in the Anatolian region, especially the Hittites. Compared to other black wine grapes, it stands out with its low tannin content, rich fruity aroma and complex structure. In good vintages, red fruits such as strawberries, cherries and raspberries stand out in the aroma profile. Although its structure is elegant, it has the potential to age and develop similar to the ‘Pinot Noir’ wine of the Burgundy region. This offers a complex aroma structure including red flowers, earth and ripe fruits.

FLAVANOL COMPOSITION OF VARIETAL AND BLEND WINES MADE BEFORE AND AFTER FERMENTATION FROM SYRAH, MARSELAN AND TANNAT

Background: The Flavan-3-ol extraction from grape skin and seed during red-winemaking and their retention into wines depend on many factors, some of which are modified in the winemaking of blend wines. Recent research shows that Marselan, have grapes with high proportion of skins with high concentrations of flavanols, but produces red-wines with low proportion of skin derived flavanols, differently to the observed in Syrah or Tannat. But the factors explaining these differences are not yet understood.