Red Wine Production
Red Wine Production can result in styles ranging from light Beaujolais to full-bodied Cabernet Sauvignon. Although the results are strikingly different, the process of production is very similar.
As opposed to other wine types, the main distinction in Red Wine Production is that the skins are allowed to macerate in the must for some period of time. This is what gives red wine its color, tannins, and allows the best to age for many years.
Destemming & Crushing Red Grapes
Immediately after arriving at the winery, the process of destemming and crushing red grapes begins. The resulting liquid is called the must and consists of skins, seeds and juice. It is important that as many stems as possible are removed, as they contain abrasive, unpleasant tannins. This is the first step in the Red Wine Production process.
Adding to Fermentation Containers
After the grapes have been destemmed and crushed, the must is pumped to a fermentation container where it settles for a few days. There are many different types of fermentation containers, from large stainless steel tanks to small oak barrels. At this time, the sugar and acidity levels are usually adjusted.
Adding Sulfur Dioxide and Yeast
The next step in the Red Wine Production process is Sulfur dioxide addition. This will prevent the must from becoming discolored or oxidized. It also destroys bacteria and other microorganisms. Although some winemakers use the naturally present yeast on grape skins for fermentation, it is far more common to add a yeast type that has been cultured in the lab. This will give the winemaker more predictable results. If cultured yeast are added, the natural yeast must first be neutralized.
Once the yeast is added, alcoholic fermentation begins. In Red Wine Production, the must is typically fermented for a shorter time, but at a higher temperature than white wine. Depending on the varietal, this process occurs between 74 and 82 degrees Fahrenheit. Whereas white wines may be fermented for a month or more, it is rare for it to take longer than two weeks for red wines.
In addition to the alcohol created by fermentation, pigments and tannins are also imparted into the must from skin contact. This part of the Red Wine Production process is called maceration, and often lasts longer than fermentation. A cap will form as released carbon dioxide pushes solids to the top of the fermentation container. Many winemakers extract additional pigments and tannins from the skins by either punching down or pumping over the cap. Some wineries have tanks called rotofermenters that turn on their sides continuously to prevent a cap from ever forming.
When the winemaker feels that enough maceration has occurred, the must is moved from its fermentation containers for pressing. A variety of methods can be used, but basket pressing is the most common for high quality Red Wine Production. Wines that will undergo oak treatment are moved to barrels at this point.
Red wine malolactic fermentation is a critical part of the Red Wine Production process. While it is optional in whites, the vast majority of red wines undergo this process. Leuconostoc bacteria are the catalyst for malo. They turn the tarter malic acid into smoother lactic acid, which is present in milk and many other dairy products.
After malolactic fermentation and any barrel aging are complete, the wine is removed from its container through a process called racking. Clear wine is racked from the top of the container to separate it from the remaining solids. The debris that remains at the bottom of the fermentation container is often used as fertilizer in the vineyard.
After racking, most red wines undergo additional clarification. Different methods are used, with some being much more invasive than others. Regardless of which clarification method is used, sulfur dioxide is added to the wine again at this point to kill any harmful microorganisms. This is typically the last step of Red Wine Production before bottling.
Bottling and Labeling
After the wine has been clarified to the vintnerís specifications, it is time for bottling and then inserting corks. It is common for wines to be aged in the bottle for some period of time before being put on the market. This will avoid selling the wines when they are agitated by bottle shock. Finally, the wine labels are affixed, and the product is ready to be enjoyed.