People have been making wine for centuries and the whole process is not just about the art but there is also a lot of science going behind the scenes. Location of the vineyard, climate, terrain, soils and other factors can greatly affect the quality of the wine, but even small mistake in a process of wine making can have a big impact on the final product.
Depending on the grapes or region, the wine making process can vary in time, technique and technology. But for most of the part, a typical wine making process includes five basic steps:
2. Crushing and pressing the grapes
4. Clarification of the wine
5. Aging and bottling the wine
The first step in the wine making process is harvesting. Harvesting can be done either by a human with shears or by a machine. Hand harvesting provides more precise selection and protects the grape’s juice content from oxidation due to damaged skins.
Harvest time determines the acidity, sweetness and flavour of the wine. Grapes are usually picked once the sugar content and acidity are in perfect balance. Once the grapes are picked, they are taken into the winery where the rotted and under ripe grapes are removed.
Crushing and Pressing the Grapes
Once the grapes are sorted, they need to be crushed and pressed in order to produce the must. Most people associate crushing grapes with feet stomping, but nowadays this process is usually performed mechanically. All the grapes are pressed in order to extract the juice and leave behind the grape skins before the fermentation starts. For the red wines, the fermentation is done together with the skin of the grape.
Fermentation is the part of the wine making process where the science comes in. Simply put, in this part of the processed sugar is being converted into the alcohol. For both the red and white wines, the yeast is added to the vats to start the fermentation.
Fermentation continues until all of the sugar is converted into alcohol. This way the final product is dry wine. In order to create a sweet wine, winemakers will stop the fermentation process before all the sugar is converted into alcohol. The process usually takes place in stainless steel tanks, large vats or oak barrels. When it comes to red wines, the skin of the grape is pressed after the fermentation is done.
After the fermentation is completed, clarification takes place. In this part of the process, the sediment caused by the dead yeast, tannins and proteins needs to be removed. This can be done with filtration and through fining.
Fining is usually done with clay, which winemakers are adding into the wine to clarify it. Unwanted particles will adhere to clay and fall to the bottom of the tank. After that filtration is done, and the sediment is captured by using a filter. Wine is now ready to bottling and aging.
Aging and Bottling the Wine
Aging the wine is one of the final stages of the process. There are two options for the winemakers in this stage: to bottle the wine or give it additional aging. Aging or cellaring the wine means storing it in an oak barrel for some time, allowing it to improve its taste.
Not all wines will benefit for aging. That’s why some of the wines are bottled right away and some of them are stored to make the wine flavours more intense. Wines that have an aging potential are the ones with high level of tannins – which is mostly red wines.