Incombustible, colourless and odourless, acid gas (also carbon dioxide) with the molecular formula CO2. Colloquially, carbon dioxide is very often incorrectly referred to as carbonic acid. In solid form as dry ice, it is used as a coolant. The gas is produced during all combustion processes and also during the respiration of animal and human beings. It also occurs in volcanic rocks and at great depths.
In the atmosphere, carbon dioxide makes up only a tiny fraction of 0.039%, but this tiny amount is indispensable for all life, because it is needed by plants during photosynthesis and oxygen is formed in the process. Since industrialisation, the proportion has increased by around 44% in connection with climate change and the associated greenhouse effect. The proportion is greater in the northern hemisphere (due to the larger land mass). The resulting extreme weather conditions with heat waves also have a negative impact on viticulture (see under decarbonisation).
Carbon dioxide content
Carbon dioxide dissolves in liquids as well as in wine depending on pressure and temperature. When it dissolves, carbonic acid is also formed by reaction with water in the smallest amount of only 0.2%. By far the largest part, however, with over 99%, is the carbon dioxide dissolved in the wine (which does not yet produce carbonic acid), which is combined with the actual carbonic acid as "free carbonic acid". As the vine grows, the sugar in the grapes is formed from carbon dioxide and water. During fermentation, the sugar is then converted into carbon dioxide and alcohol.
At 1.98 g/l, carbon dioxide is about 1.5 times heavier than air. Therefore, there is a danger of suffocation in the fermentation cellar if...
