Monitoring Gaseous CO2 and Ethanol above Champagne Glasses: Flute versus Coupe, and the Role of Temperature

In champagne tasting, gaseous CO2 and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO2 and ethanol was monitored through micro-gas chromatography (μGC), all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of champagne was served into a flute or into a coupe. The concentration of gaseous CO2 was found to be significantly higher above the flute than above the coupe. Moreover, a recently developed gaseous CO2 visualization technique based on infrared imaging was performed, thus confirming this tendency. The influence of champagne temperature was also tested. As could have been expected, lowering the temperature of champagne was found to decrease ethanol vapor concentrations in the headspace of a glass. Nevertheless, and quite surprisingly, this temperature decrease had no impact on the level of gaseous CO2 found above the glass. Those results were discussed on the basis of a multiparameter model which describes fluxes of gaseous CO2 escaping the liquid phase into the form of bubbles

Effervescence in champagne and sparkling wines: From grape harvest to bubble rise

Bubbles in a glass of champagne may seem like the acme of frivolity to most of people, but in fact they may rather be considered as a fantastic playground for any fluid physicist. Under standard tasting conditions, about a million bubbles will nucleate and rise if you resist drinking from your flute. The so-called effervescence process, which enlivens champagne and sparkling wines tasting, is the result of the complex interplay between carbon dioxide (CO2) dissolved in the liquid phase, tiny air pockets trapped within microscopic particles during the pouring process, and some both glass and liquid properties. In this tutorial review, the journey of yeast-fermented CO2 is reviewed (from its progressive dissolution in the liquid phase during the fermentation process, to its progressive release in the headspace above glasses). The most recent advances about the physicochemical processes behind the nucleation, and rise of gaseous CO2 bubbles, under standard tasting conditions, have been gathered hereafter. Let's hope that your enjoyment of champagne will be enhanced after reading this tutorial review dedicated to the unsuspected physics hidden right under your nose each time you enjoy a glass of bubbly

Hétéro-nucléation de cristaux de neige carbonique au débouchage d’une bouteille de champagne

Le débouchage d’une bouteille de champagne permet de revisiter la physique des changements de phase qui accompagnent la détente adiabatique du volume de gaz sous pression dans le col de la bouteille. On s’intéresse ici aux phénomènes de condensation qui apparaissent dans le sillage du bouchon qui saute, en fonction de la température de ladite bouteille. Pour les bouteilles stockées à 20 °C, un panache bleu azur apparait dans le col de la bouteille et dans le sillage du bouchon qui saute. Il s’évanouit au bout de quelques millisecondes. On montre que ce panache bleu est la signature de la transformation en cristaux de neige carbonique et par nucléation hétérogène, de la vapeur de dioxyde de carbone présente dans le col de la bouteille

Bubbles in Titan’s Seas: Nucleation, Growth, and RADAR Signature

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