There are two reasons to filter wine: aesthetics and microbial stability. On the aesthetic side, filtration can make a wine more polished both in the glass and in the mouth; often creating a rounding effect that softens the wine’s edges. If your wine is sound with no flaws, then you can decide if you want to further shape your wine by filtering it. However, if you have residual sugar or Malic acid left in the wine, or there was a problem with Acetobacter or Brettanomyces during the ageing/storage period, then filtration is no longer an artistic decision; it becomes the only way to guarantee microbial stability for the wine.
How Filtration Works:
Pore sizes of filters are measured in microns. Typical winemaking sizes are 5, 3, 2, 1, and .45 micron media. The smaller the holes, the “tighter” the filter is said to be. Filtration’s guarantee of microbial stability comes from the fact that the pore size of filters can be made smaller than the actual yeast and microbes themselves. As the wine passes through the filter the larger microbes become stuck and are removed from the wine. Note: 2-micron filters are used to remove yeast, and .45-microns are needed to remove bacteria.
"Absolute" & "Nominal":
Filters are rated as being “Nominal” or “Absolute”. A nominal filter will remove most particles that are equal or greater than the rated micron size. An absolute filter will remove all particles larger than the micron rating.
If you are filtering a small amount of wine we recommend our round plate wine filter. If you are already using an enolmatic bottle filler to bottle your wine you might check out inline filter for that system that allows you to filter as you bottle. For larger volumes of 30 plus gallons you will probably want to look at our higher volume plate filters for filtering your wine.