terclim by ICS banner
IVES 9 IVES Conference Series 9 MAPPING THE CONCENTRATIONS OF GASEOUS ETHANOL IN THE HEADSPACE OF CHAMPAGNE GLASSES THROUGH INFRARED LASER ABSORPTION SPECTROSCOPY

MAPPING THE CONCENTRATIONS OF GASEOUS ETHANOL IN THE HEADSPACE OF CHAMPAGNE GLASSES THROUGH INFRARED LASER ABSORPTION SPECTROSCOPY

Abstract

Under standard wine tasting conditions, volatile organic compounds (VOCs) responsible for the wine’s bouquet progressively invade the glass headspace above the wine surface. Most of wines being complex water/ethanol mixtures (with typically 10-15 % ethanol by volume), gaseous ethanol is therefore undoubtedly the most abundant VOC in the glass headspace [1]. Yet, gaseous ethanol is known to have a multimodal influence on wine’s perception [2]. Of particular importance to flavor perception is the effect of ethanol on the release of aroma compounds into the headspace of the beverage [1]. Moreover, triggered by the presence of ethanol in wines, the Marangoni effect increases the exhaust of flavored molecules in the glass headspace [2]. In addition, ethanol is known to modify the orthonasal detection threshold of aromas (and especially the fruity aromas [2]), and it can also trigger the trigeminal system leading to tingling and/or warm sensation [2]. Monitoring gaseous ethanol, in space and time, in the headspace of wine glasses is therefore crucial to better understand the neuro-physicochemical mechanisms responsible for aroma release and flavour perception.

For this purpose, micro-gas chromatography was used in the past to simultaneously monitor gas-phase ethanol and CO₂ in the headspace of champagne glasses, but with a relatively poor temporal resolution leading to a one-minute data sampling interval [3], [4]. Since the last decade at GSMA (Groupe de Spectrométrie Moléculaire et Atmosphérique), tunable diode laser absorption spectroscopy has shown to be a well-adapted method to accurately monitor gas-phase CO₂ in the headspace of glasses poured with champagne [5]. The tunability of semiconductor laser with current modulation provides CO₂ monitoring with a high temporal resolution of 42 measurements per seconds. Lastly, thanks to the recent interband cascade laser (ICL) technology, the CO₂ sensor was upgraded to monitor gaseous ethanol. This new quantum laser source, combined with previous technology developed for the monitoring of gas-phase CO₂, al-lowed us to simultaneously monitor gas-phase CO₂ and ethanol under standard still wine and sparkling wine tasting conditions. The first data sets obtained in the headspace of a glass poured with a standard brut-labelled Champagne wine are presented.

 

1. G. Liger-Belair and C. Cilindre, “Recent Progress in the Analytical Chemistry of Champagne and Sparkling Wines,” Annu. Rev. Anal. Chem., vol. 14, pp. 21–46, 2021.
2. C. M. Ickes and K. R. Cadwallader, “Effects of Ethanol on Flavor Perception in Alcoholic Beverages,” Chemosens. Percept., vol. 10, no. 4, pp. 119–134, Dec. 2017.
3. C. Cilindre, A. Conreux, and G. Liger-Belair, “Simultaneous monitoring of gaseous CO₂ and ethanol above champagne glasses via micro-gas chromatography (μGC),” J. Agric. Food Chem., vol. 59, no. 13, pp. 7317–7323, 2011.
4. G. Liger-Belair, M. Bourget, H. Pron, G. Polidori, and C. Cilindre, “Monitoring gaseous CO 2 and ethanol above champagne glasses: Flute versus coupe, and the role of temperature,” PLoS One, vol. 7, no. 2, pp. 1–8, 2012,.
5. A. L. Moriaux et al., “How does gas-phase CO₂ evolve in the headspace of champagne glasses?,” J. Agric. Food Chem., vol. 69, no. 7, pp. 2262–2270, 2021.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Florian Lecasse¹, Raphaël Vallon¹, Vincent Alfonso¹, Bertand Parvitte¹, Clara Cilindre¹, Virginie Zeninari¹, Gérard Liger-Belair¹

1. Groupe de Spectrométrie Moléculaire et Atmosphérique (GSMA), UMR CNRS 7331, UFR Sciences Exactes et Naturelles

Contact the author*

Keywords

Ethanol, Champagne, Interband Cascade Laser, Spectroscopy

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

DETERMINATION OF FREE AMINO ACIDS, AMINO ACID POTENTIAL AND PROTEASE ACTIVITY IN THE LEES AND STILL WINES OF CHAMPAGNE

Prior to winemaking, organic or mineral nitrogen compound concentrations are usually measured in the vineyard and in grape musts. These indicators facilitate vine cultivation decisions, usually through yield or vigor. During vinification, yeast and bacteria metabolize nitrogen compounds in the musts in order to generate biomass. After fermentation, the microorganisms rerelease a part of this nitrogen as soluble compounds into the wines. Another part remains bound in the lees and can be lost during racking. The must’s natural nitrogen quantities, additional supplements during fermentation, and lees contact management enhance the release of nitrogen compounds to the wines. During ageing these nitrogen compounds – primarily the amino acids – are implicated in the generation of odorous compounds such as heterocycles(1).

NOVEL BENZENETHIOLS WITH PHENOLS CAUSE ASHY, SMOKE FLAVOR PERCEPTION IN RED WINES

Smoke impacts on wines are becoming a worldwide problem; the size and severity of wildfires increasing due to influences from changing climates.¹ For over a century, wines have been known to have a unique issue of absorbing chemical compounds derived from wildfire smoke wherein the flavor of the subsequent wine becomes ashy, rubbery, campfire-like, and smoky.² The economic impacts of a smoke-impacted wine can last for years depending on the grape varietal, costing Oregon and Washington states in the United States over a billion dollars from the 2020 wildfires, as an example.³ While years of research have indicated elevated concentrations of smoke-related compounds, such as guaiacol and syringol, in wines after smoke events, unfortunately, replicating the sensory experience using smoke-associated phenols has not had much success.⁴

WINE WITHOUT ADDED SO₂: OXYGEN IMPACT AND EVOLUTION ON THE POLYPHENOLIC COMPOSITION DURING RED WINE AGING

SO₂ play a major role in the stability and wine during storage. Nowadays, the reduction of chemical input during red winemaking and especially the removing SO₂ is a growing expectation from the consumers. Winemaking without SO₂ is a big challenge for the winemakers since the lack of SO₂ affects directly the wine chemical evolution such as the phenolic compounds as well as its microbiological stability.

WINE AS AN EMOTIONAL AND AESTHETIC OBJECT: IMPACT OF EXPERTISE

Wine tasting has been shown to provide emotions to tasters (Coste et al. 2018). How will expertise impact this emotional response? Burnham and Skilleås (2012) reported that the cultural, experiential, and aesthetic competencies characterize an expert in wine compared to a novice. Although there is no consensual definition of an aesthetic experience, Burnham and Skilleås (2012) reported that aesthetic appreciation is “disinterested, normative for others and communicable” in comparison to sensory pleasure.

TANNINS AND ANTHOCYANINS KINETICS OF EXTRACTION FROM ARINARNOA, MARSELAN AND TANNAT UNDER DIFFERENT WINEMAKING TECHNIQUES

Marselan wines have an unusual high proportion of seed derived tannins from grapes having high proportions of skins, which are rich in tannins. But the causes behind this characteristic have not yet been identified. In vintage 2023 wines were made at experimental scale (9 kg by experimental unit) from Arinarnoa, Marselan and Tannat Vitis vinifera grape cultivars by traditional maceration, and by techniques aimed to increase the wine content in skin derived tannin: addition of extraction enzymes, addition at vatting of grape-skin enological tannins, or by extended maceration, known to increase the seed derived tannin contents of wines.