Fermentation
The production of alcohol consists of several processes from crop to final product on the shelves. The fermentation is the first process where the alcohol itself is made. The subsequent processes (e.g. distillation and maturation) extract it and make the taste more pleasant.
How alcohol is formed
Alcohol (ethanol) is made using the fermentation process. During the process, yeast converts sugar into carbon dioxide and alcohol. For fermentation to take place, the following three things must be present:
It is important that there is no air present, otherwise the yeast will produce ethanoic acid (a chemical found in vinegar).
Yeast
Yeast is found everywhere. It's in the air we breathe and covers the skin of fruit in the hope of absorbing some sugar. You don't have to hunt for yeast. Leave a bowl of flour and water and yeast will find it. Yeasts are small unicellular fungi that contain special enzymes that create the reaction that forms alcohol. As I said, yeast occurs in natural form, but also as a cultivated or pre-cultivated product, as we know it from the supermarket. However, there are quite a few species of yeast, especially those in the Saccharomycetales genus, that are of interest to brewers and distillers due to their efficiency in fermentation.
Sugar
Sugar is found naturally in most crops, plants, fruits and berries, e.g. molasses or juice from sugarcane is used in the production of rum. Which sugar is used has a big influence on the final spirit. Therefore, the production of different types of spirits prescribes specific crops.
This is how the fermentation process is carried out
During fermentation, the sugary crop and yeast are mixed in water, where the temperature of the liquid is kept constant so that fermentation can take place. When fermentation begins, the yeast “eats” the sugar, converting it into alcohol and carbon dioxide. As the sugar is converted into alcohol, the percentage of alcohol in the liquid increases, and the alcohol actually ends up killing the yeast bacteria. So they die in their own waste. Depending on the yeast in question, this will happen at an alcohol percentage of around 15. This means that you are left with a mixture of alcohol and water when the fermentation is over.
What do you do after fermentation?
After the fermentation is over, you are left with an alcoholic liquid. This is where the journey actually ends for e.g. beer and wine, but for the production of spirits, the liquid must be distilled. This is the process where you separate the alcohol from the rest of the liquid and this means that you can achieve an alcohol percentage higher than 15%. Like fermentation, distillation also has a big impact on the final spirit.