The term 'alcohol' is often used superficially in the sense of wine. Alcohols or alkanols represent a powerful environment in terms of diversity. The most important (monovalent) alcohol in wine is called ethyl alcohol (ethanol, ethyl alcohol) or wine spirit. It is obtained from dextrose and fructose during fermentation, or the sugar molecules are broken down to ethyl alcohol with the help of yeast during the fermentation process. The extremely toxic methyl alcohol (methanol) or wood alcohol can be considered lethal for humans even in the smallest quantities.
During fermentation, further 'medium' and 'higher' alcohols are formed, which are called fusel oils, among others. Although they only exist in relatively small amounts in wine, these alcohols are enormously influential, generally toxic and also partly narcotic. However, they determine, among other things, extremely important odour and taste characteristics of a wine. Moreover, they attribute a certain 'permanence' to ethyl alcohol - even after the wine has been consumed in the human body. In case of excessive consumption of wine, they are very well responsible for the well-known 'hang-over'.
Another important companion of a wine from the alcohol family is the precious glycerine.
It should also be noted that ethyl alcohol (ethanol or commonly referred to as 'the alcohol') does not (as is often believed) simply 'evaporate, burn, evaporate' quickly when boiled with wine. This (erroneous) logic is often inferred from the fact that the boiling point of alcohol is reached much earlier (78.3°C or 173ºF ) than the boiling point of water (100°C or 212°F). In reality, however, water and alcohol are hardly easily separated in the mixture and, more or less together, shift the boiling points (in relation to the water/alcohol ratio) somewhere between 78.3° and 100°. Thus, for example, if the mixture at boiling is by far predominantly water and contains very little alcohol, the boiling point will correspondingly be only slightly below the typical boiling point of water. If the mixture is againunm predominantly alcohol, then the boiling point will approach that of the alcohol accordingly. As the alcohol evaporates, the alcohol content of the mixture in the liquid phase decreases progressively, while the boiling point increases correspondingly and the alcohol content in the vapor phase decreases. Physicists additionally qualify the water and alcohol mixture as a so-called 'azeotropic mixture' if the liquid and the vapor have exactly the same composition (and thus cannot be further distilled). In the case of alcohol (or ethanol) and water, the so-called 'azeotropic point' occurs at 96%vol ( 96% alcohol and 4% water). However, what does all this mean for us chefs and epicures in practice? Very little. Fortunately, however, there are already studies with some practical points of view:
In 1992, a study by the University of Idaho, Washington State University, and the U.S. Food and Drug Administration (USDA) proved that a wonderful dish such as coq au vin (where the wine is, of course, a natural part of the preparation) is ultimately served with 4% to 49% of the original alcohol after cooking. The same is true for the delicious flambéed bananas in our recipes section: the flambe has only helped itself to about 20% of the total alcohol after going out.
The amount of alcohol remaining is co-determined by many variables when cooking (e.g. temperature, design of cooking vessels, with or without lid, duration of cooking...). In practice, this means that if a dish is uncooked (or prepared for cooking later) and stored in the refrigerator overnight, almost all of the alcohol will be available in the dish the next day. Again, should the alcohol not be added until the dish is cooked and the dish removed from the flame immediately afterwards, then approximately 70% of the alcohol will remain. If a dish is mixed with alcohol and cooked for only 15 minutes, then about 40% of the alcohol will remain. After one hour, just about 25% remains. After 2.5 hours, only about 5% remains. Thus, the longer we cook our dish with alcohol, the lower the remaining alcohol content will be.