What is the difference between fining and filtering?

The distinction between fining and filtering in winemaking is best captured by the fact that fining involves the addition of substances, such as egg whites or other fining agents, to the wine in order to bind with undesirable components, which can then be removed, improving the wine's overall clarity and taste. This process helps to adjust the wine's mouthfeel and flavors by removing excess tannins, phenolic compounds, or other components that might lead to bitterness or instability.

Filtering, on the other hand, is a physical process that involves passing the wine through a membrane or a series of filters to remove particulates, yeast, bacteria, and other solid matter, enhancing the wine's clarity and stability. A well-filtered wine looks visually appealing and is less likely to develop faults during storage.

In contrast, other options suggest incorrect associations, such as the idea that fining adds tannins or that it is meant for aging or sweetness, which do not accurately represent the primary functions of these winemaking techniques. Fining and filtering are distinct processes that serve specific and different purposes in the production of quality wines.