Q. Why are some wines filtered? Aren’t the unfiltered ones always better?
A. By removing small particles, filtering clarifies and reduces sediment. It can also stabilize wine so that unwanted bacteria and yeasts don’t wind up creating spoilage problems after bottling. Many experts agree, however, that filtration can also rob wine of some of its flavor and character.
Fortunately, filtration doesn’t have to be an all-or-nothing proposition. For instance, a winemaker may decide that a certain wine needs only light filtration, another wine none at all, and that still another requires a thorough scrubbing to stave off funky-smelling spoilage bacteria. In any case, for preserving flavor, the best filtering is the least amount that’s absolutely necessary, and judging this takes skill. So you might say, when it comes to filtering, the very best winemakers always know when to say when.