You may mean in a bottle where something like yeast or bacteria were doing anaerobic respiration using alcoholic fermentation. Glycolysis, the first step of anaerobic respiration, breaks glucose (6 Carbons) into a pair of pyruvate (3 C). Alcoholic fermentation converts the very toxic pyruvate into the slightly less toxic ethyl alcohol (2 C) and CO2. The CO2 released would be what makes the bubbles in beer and champagne, so when you open the bottle, you'll hear the extra gas come out.Your body does anaerobic respiration when it can't get enough O2, but it produces lactic acid which still has 3 Carbons, so there's no release of CO2 gas. You only release CO2 gas when you do aerobic respiration and break the pyruvate all the way down to 3 CO2 molecules.