An introduction to winemaking - Part 1
Techniques and processes for red wines
Hello, everyone! I’m officially back from my break and plan to regularly produce new wine-related content again. The past few weeks have seemed like two months to me. I recently decided to leave my day job to focus on my gaming company, and it has been a serious whirlwind getting things started. That’s not what you all are here to talk about, though. We’re all here for the wine.
While I nail down the ultimate direction for the next chapter in this series, I thought it would be interesting to cover the basic winemaking process, starting just after process and leading up to maturation. Even over these few weeks, I found many people were curious about the process and gave more or less detailed accounts on many occasions. I’ll even be sharing some first-hand experience from my own foray into winemaking. Ready to learn?
What are we talking about?
When I say winemaking, what do I really mean?
In this case, I’m specifically referring to the vinification process which occurs in a winery. This is not all that goes into making a wine of course, but it is a common point where human (or machine) hands turn those freshly harvested grapes into a young wine, ready for maturation or release depending on the style. This process does also differ quite a lot between red and white wines. Most rose styles are produced using a combination of the techniques from both. I’ll leave white and rose for another time. Let’s focus on the red!
Processing the grapes
In general, the winery process starts just after harvest. Grapes are received at the winery and will often undergo an initial sorting procedure. There are various human and mechanized methods to this, but the goal is to increase the quality of the wine by discarding fruit which is less ripe, bruised, or diseased as well as removing non-grape matter like leaves and large stems. Usually higher quality wines undergo significant sorting while many high volume wines may not be sorted at all. As you can imagine, since sorting is extra work it also increases the production cost and therefore sale price of the final wine.
Following the optional sorting, grapes for most styles of red wine will be crushed. There are various methods to this, though commonly it is done via a special crushing machine for all quality levels. Remember the foot treading in lagares from our journey through Port? That is a very old school method of crushing which uses human feet. In some cases, you may have heard of festivals in wine regions where guests can stomp on the grapes. Usually this is just for fun rather than part of actual production. Regardless of method, crushing breaks the skins of the grapes and releases their juice. It also releases some initial color, via a red-pigmented molecule called anthocyanin, and tannins, which are what give red wines texture and a bit of astringency. The crushed grapes and juice will all be combined together in a typically open-topped vessel to begin fermentation.
Turning juice to wine
Once in the fermentation vessel, be it oak, concrete, or stainless steel, the juice and skins will continue to soak while yeast do their work turning the sugars in the juice into alcohol (ethanol predominantly). However, this isn’t a time to just let things be. During this stage is when the winemakers are doing serious work with what is called cap management. Remember all those grape skins? They float to the top of the liquid, pushed by carbon dioxide, and form a fairly thick “cap” on the top of the fermenting must. While the skins are not in the liquid, extraction of color, tannin, and flavor isn’t happening. They are also exposed and a if dry for too long can spoil. Nobody wants spoiled wine. Winemakers prevent spoilage and encourage extraction by “managing” the cap, typically by punching it down into the juice with a large paddle, or spraying juice over the top. A combination of both techniques is frequently used and these occur several times per day for most red wines over about one to three weeks. To give you an idea, here’s a video of me punching down the cap on my 2019 Sangiovese with a very special tool that is definitely not a potato masher. Now imagine this 10 to 1000 times larger in a commercial winery, across multiple vessels.
Towards the end of fermentation, when the yeast have converted most of the sugars in the must into alcohol, the a press will be used to separate the juice from the skins. Precisely when this happens is up to the winemakers discretion, but typically this occurs when a sufficient color, tannin, and phenolic extraction has taken place. Very frequently, different stages of juice separation by pressing are stored separately and either used for different wines or for blending options closer to bottling. The earliest pressing, the free run juice, simply runs from the press on it’s own without pressure applied, other than that from the weight of the grapes. This free run juice is usually the lightest in color and tannin, though can still be quite intense depending on prior treatment. As pressing continues, the later fractions have increasingly higher tannin and phenolic content. These may be held aside for blending or bottled as a separate bottling from the free run juice. To show you another very small scale example, here is a photo of the pressed skins from my wine above.
On to the bottling line
After pressing, fermentation will continue until completion in a vessel of the winemakers choosing. These can be stainless steel, concrete, or oak of varying age and toast level. It all depends on the style of wine and what the winemakers wants in the finished product. The wine may undergo long maturation in this vessel, be transferred to another vessel for maturation, or simply bottled and sold immediately.
Speaking of bottling, that brings us to the end of this very generalized journey in red wine production in the winery. Hopefully you understand a bit more about the process and maybe you can spot some of the tools I’ve discussed the next time you visit a winery! Note that the winemaking process can vary significantly depending on the desired style, grape varieties, price point, and winemaker. We’re only scratching the surface but I’ll be going into more detail when I discuss specific wines in the future!
Until next time!