How does the concentration of dissolved carbon dioxide affect the perceived acidity and mouthfeel of sparkling wine?

The concentration of dissolved carbon dioxide (CO2) significantly affects the perceived acidity and mouthfeel of sparkling wine. Dissolved CO2 contributes to the perceived acidity through a phenomenon known as carbonic bite. When CO2 dissolves in water (and wine, which is mostly water), it forms carbonic acid (H2CO3). While carbonic acid is a weak acid, it stimulates trigeminal nerve endings in the mouth, creating a tingling or prickling sensation that is perceived as acidity. This carbonic bite enhances the wine's overall freshness and liveliness. Higher concentrations of dissolved CO2 result in a more pronounced carbonic bite, making the wine seem more acidic. However, this perceived acidity differs from the acidity derived from organic acids like tartaric, malic, and lactic acids. Dissolved CO2 also significantly affects the mouthfeel of sparkling wine. The bubbles, created by the release of CO2, contribute to the wine's texture and effervescence. These bubbles stimulate mechanoreceptors in the mouth, creating a creamy, frothy sensation. The size and persistence of the bubbles are influenced by the concentration of dissolved CO2, as well as factors like the wine's viscosity and the presence of surfactants (surface-active agents). Higher concentrations of dissolved CO2 result in smaller, more persistent bubbles, contributing to a finer and more elegant mousse (the creamy foam in sparkling wine). The release of CO2 also helps to lift volatile aroma compounds from the wine, enhancing its aromatic intensity and complexity. Therefore, the concentration of dissolved CO2 is a crucial factor in determining the overall sensory profile of sparkling wine, influencing both its perceived acidity and mouthfeel. Winemakers carefully control the level of dissolved CO2 during the production process to achieve the desired style and quality.