Although it may seem like a magic trick, the truth is that behind any bottle of wine is a unique chemical process capable of transforming a simple fruit juice into an elegant drink. A process that did not have any technical improvements until the nineteenth century. This is a way of understanding the reason why wine looks, tastes , and even feels the way it does. We have already seen the first part of the process that involves the preparation of wine before being tasted. Keep reading the second part of how wine is made.
Ancient cultures that processed wine have always used yeast. This was naturally done, believing that fermentation was the result of a chemical catalyst and not an invisible process such as these microorganisms. However, with Pasteur’s first research on the fermentation process, it was understood that yeasts consume sugars generating two key elements: carbon dioxide and ethanol. In addition yeasts have the ability to create other substances such as glycerin, acetic and lactic acids.
However, despite the importance of these microorganisms, it’s interesting to know that their role in the fermentation of wine only lasts between two and three days. There are three important factors in the fermentation of an excellent quality wine to be considered
- Density: It allows us to know how much the grape juice lacks to turn completely into an alcohol.
- Temperature: If the temperature it’s very low it could eliminate prematurely the yeasts, which would block the process of fermentation. On the other hand, a high temperature will cause the loss of aromatic elements and an increase of the bitterness.
- Air contact or The Pasteur effect: During wine fermentation a small contact with air will stop the process, that’s why the fermentation tanks close tightly.
Storage and Filtration
It is the slow oxygenation of the wine, that absorbs pigments and flavors from the wood. The maturation was done in wines from ancient Egypt that preserved wine in clay vases, but it was the Romans who learned the technique of preserving wine in oak barrels. The influence of wood on wine is complex and there are many studies on the chemistry of maturing in oak barrels. They spend between six months and a year in wooden barrels and then rest in the bottle until the third year after its elaboration. This ageing time improves the qualities of the product and balances aromas and flavours.
After ripening, the wine goes through a filtration process. In this stage the residues and sediments are eliminated. Filtration eliminates any residue from the winemaking process, ensuring the physical-chemical stability of the wine and microbiological stability. Although before this step was obvious, now it is very important and provides better quality of texture, aroma and flavor.
Bottling is a quite recent operation. It began when it was possible to produce more robust and affordable glasses. Primitive wine bottles had a convex shape. Bottling is a set of operations (generally done mechanically) for the final conditioning of the wine in order to make its expedition and final sale to the consumer. The current bottles have a standard volume of 750 ml. An important element in bottling is the encapsulation that can use natural (cork stoppers), semi-synthetic, synthetic and metal capsules. All of them have special and unique characteristics.
Interesting, isn’t it? It’s a process with centuries of history behind it, with hundreds of variants and possibilities. If you’d like to see the first steps to produce a high quality wine click here. After theory comes practice, so if you’d like to know more about wines, you have to taste it. We recommend you to try some of unique Melis’ Mediterranean artisan wines.