Bubbles in alcoholic beverages, primarily found in sparkling wines, add a unique effervescence and sensory experience. These drinks are characterized by their distinct fizz, which influences their taste, aroma, and how alcohol is absorbed by the body. The presence of carbonation creates a dynamic interaction with the beverage and the consumer’s physiology. This article explores these bubbly drinks, from their production to their impact on the human system.
Understanding Sparkling Alcoholic Beverages
Sparkling alcoholic beverages are wines that contain dissolved carbon dioxide, creating their characteristic fizz. Well-known types include Champagne, Prosecco, Cava, and Sekt, each distinguished by their origin, production methods, and grape varietals.
Champagne, from the Champagne region of France, is made primarily from Chardonnay, Pinot Noir, and Pinot Meunier grapes using the traditional method. This method contributes to its fine, persistent bubbles and complex flavors.
Prosecco, an Italian sparkling wine from the Veneto and Friuli-Venezia Giulia regions, is predominantly made from Glera grapes. Unlike Champagne, Prosecco typically undergoes secondary fermentation in large stainless steel tanks using the Charmat method, resulting in bigger, softer bubbles and often a fruitier, lighter, and sweeter profile.
Cava, a Spanish sparkling wine mainly produced in Catalonia, also uses the traditional method like Champagne. It is made with native grapes such as Macabeo, Xarel-lo, and Parellada, often yielding an earthy taste with notes of almond and lemon zest. Sekt, a German sparkling wine, is frequently produced using the Charmat method and can be made from various grapes like Riesling, Pinot Noir, or Pinot Blanc, often having varying sweetness levels.
The Science of Carbonation
The effervescence in sparkling alcoholic beverages stems from dissolved carbon dioxide (CO2) gas. This CO2 is introduced either through natural fermentation or artificial injection. In the traditional method, used for Champagne and Cava, secondary fermentation occurs directly in the sealed bottle after initial fermentation. Yeast consumes added sugar, producing alcohol and CO2, which becomes trapped under pressure within the bottle.
Alternatively, the Charmat method, common for Prosecco and many Sekts, involves secondary fermentation in large, pressurized tanks, which is a faster and less expensive process. Once the wine is poured into a glass, the dissolved CO2 seeks to escape into the atmosphere. This escape is facilitated by nucleation sites, which are microscopic imperfections or particles often found on the glass surface. These tiny gas pockets act as starting points where CO2 molecules can aggregate, overcoming the energy barrier required for bubble formation.
As CO2 molecules diffuse into these gas pockets, bubbles grow and detach, rising in visible “trains” to the surface. During their ascent, these bubbles continue to expand as more dissolved CO2 enters them, and they also collect surfactant molecules from the wine. Upon reaching the surface, the bubbles burst, releasing aroma compounds and creating the characteristic foam that is integral to the sensory experience of sparkling wines.
How Bubbles Affect Alcohol Absorption
The carbonation in sparkling alcoholic beverages can influence how quickly alcohol is absorbed into the bloodstream. Alcohol is absorbed slowly from the stomach but rapidly from the small intestine. The rate at which alcohol is absorbed is directly related to the rate of gastric emptying; faster emptying leads to faster absorption and higher peak blood alcohol concentrations.
Carbonated drinks can accelerate gastric emptying, potentially leading to a quicker passage of alcohol from the stomach into the small intestine. This accelerated transit can result in alcohol entering the bloodstream more rapidly than with non-carbonated alcoholic beverages. Scientific observations suggest that the effervescence may increase the surface area for absorption in the stomach or promote the opening of the pyloric sphincter, which controls the flow of contents from the stomach to the small intestine.
While the overall amount of alcohol absorbed remains the same for a given dose, the speed of absorption can influence the onset and intensity of intoxication. Therefore, the perception that sparkling alcoholic beverages lead to faster intoxication is supported by the physiological mechanism of enhanced gastric emptying, even though the total alcohol consumed is the primary determinant of overall blood alcohol concentration.
Serving and Storing Sparkling Drinks
Proper serving and storage techniques preserve the quality and enhance the enjoyment of sparkling alcoholic beverages. For optimal flavor and effervescence, most sparkling wines should be served chilled, typically between 41°F (5°C) and 45°F (7°C). Serving them too warm can make them overly frothy and diminish their vibrant flavors.
Glassware choice also affects the drinking experience. Traditional flute glasses, with their tall and narrow design, preserve bubbles and direct aromas toward the nose, maintaining a steady stream of effervescence. Coupe glasses offer a wider surface area that can initially release more aroma, but they also cause carbon dioxide to dissipate more quickly, leading to a flatter drink sooner. Tulip-shaped glasses, slightly wider than flutes but tapered at the rim, offer a balance, allowing for aroma concentration while supporting bubble longevity.
For storage, sparkling wines should be kept in a cool, dark place with consistent temperatures, ideally between 45°F (7°C) and 55°F (13°C), and 50% to 80% humidity to prevent the cork from drying out. Store corked bottles horizontally to keep the cork moist, to maintain a proper seal and prevent premature oxidation. When opening a bottle, chill it thoroughly, then hold the cork firmly while twisting the bottle slowly from the base, allowing pressure to release gradually to prevent a forceful pop and potential injury.