In some wines, as we approach to the bottom of the bottle, we witness large particles as well as liquid, coming into the wine glass. These particles, which we call sediment and which seem like an annoying defect at first glance, are actually integral parts of the wine. But in order not to spoil the taste of wine drinkers, producers take various measures to prevent these particles from passing into the bottle. Filtration is the most common among these measures.

You will remember that we serve a wide variety of wines (more than 450 varieties) at WAYANA Wine House in Kadikoy. The majority of the wines we feature in the WAYANA Wine Menu have the phrase 'limited filtration applied' on their labels. But some of the wines we serve also have a more specific message on the label: 'no filtration' or something similar. Since filtration is an important part of wine production, it is worth spending some time to understand the essence of the process.

If we are going to talk about filtering, we first need to look at what is filtered. Let's briefly remember the wine production process. Wine is obtained by converting the natural sugar in the grape must by squeezing the harvested grapes, into alcohol by the wine yeast (chemically called fermentation). When this process is completed, the resulting raw wine has a cloudy appearance. The reason why the wine is cloudy is the yeast residues and microbes left over from fermentation. Filtration is applied to the wine to prevent these residues from passing into the bottle.

Two basic filtration processes are applied to wine. These are named by sequence numbers. The first filtration is to remove cloudiness from the wine after fermentation and targets yeast residues. The second filtration is to remove bacteria before bottling.

Filtration is definitely used in the production of some wines. Wines produced in large quantities, sweet white wines and wines with botrytis (noble mold) are in this group. Some wines are not filtered, but the wine is rested in the tank to remove the cloudiness of the wine. During this resting process, yeast particles settle to the bottom of the tank under the influence of gravity. After the settling process is completed, the wine in the upper part of the tank, which is now clear, is siphoned and removed from the tank.

Wines that do not undergo filtration include white wines in oak barrels, red wines produced in small quantities, and wines that undergo malolactic fermentation after the main fermentation. It is important to keep in mind that unfiltered wine production is more difficult and the risk is higher.

The most important risk is the danger of wine turning into vinegar. We tend to see wine as a static liquid, but in fact, wine is an organic structure that is constantly changing. This change is sustained by the bacteria in the wine, and one of the possible consequences is that the wine goes bad. The first way to control bacteria is to filter them and clean them from the inside. The second way is to apply a second fermentation, malolactic fermentation, at the risk of reducing the fruity identity. In this case, the risk of spoilage after bottling is eliminated, and the wine gains a structure with more cream and nuts. A third way is to not apply filtration but increase the sulfite dose.

The wine expert decides which method to choose in filtration. There are many examples of each application that work very well. In this respect, there is no general rule that it becomes a good or bad wine because it is filtered or not. But we, wine-lovers, need to know that sediment is not a wine defect, sediment is a natural part of the wine, and we need to take into consideration that wine with sediment is not spoiled.