Term for the alcohol content (also total alcohol content) in wine before any enrichment; see under alcohol content.
The alcohol content of wine refers to the proportion of ethanol; the main type of alcohol present. The theoretically achievable alcohol content of a wine can already be calculated in the grapes by the must weight. It results from the sugar (fructose and glucose) in the must, which is converted into alcohol and carbon dioxide during fermentation. In the 19th century, the chemist Joseph Gay-Lussac (1778-1850) developed a system that represents the alcohol content in degrees (°), which is still partly used in Anglo-American countries. Today, however, the indication in percent by volume is internationally common and standardised within the EU. The measurement is made at a temperature of 20 °Celsius.
There are four different terms for alcohol content. The main interest is in how much alcohol is actually contained in the drink. In most countries, the actual alcohol content is indicated on the label:
potential alcohol content
Theoretical proportion that would be additionally possible through complete fermentation of the residual sugar. In Italy, this value is often given after the existing alcohol content in the form of e.g. "14% vol+4". In the concrete case, this means a residual sugar of converted 4% alcohol, which is about 65 g (1% alcohol corresponds to 16 to 17 g sugar).
Total alcohol content
Sum of existing and potential alcohol content.
natural alcohol content
Total alcohol content before any enrichment.
During fermentation, 10 grams of sugar per 1,000 grams of must yield 0.66% alcohol by volume. A content of 8 grams of alcohol per litre corresponds to about 1° or 1% vol. The conversion formula is % vol x 7.894 = grams of alcohol per litre (g/l) of wine. At 12% vol, this gives 94.7 g/l. In a 0.75 litre bottle of wine, this is 71 g of pure alcohol. An eighth of wine contains approximately the same amount of grams of alcohol as it has percent by volume. This means that in an eighth of wine with 12%...