Wine does tend to invite and divide opinion, among both producers and drinkers. Trends come and go (although some actually stay…), and one recent topic of discussion is unfiltered wines.

Some producers and oenophiles see unfiltered as the purest expression of the grape, whereas others can’t get past the dodgy homebrew images that haunt them (maybe after some dodgy homebrew). Lots of producers are turning out unfiltered wines in greater quantities, so are unfiltered wines better?

Why is wine filtered?

Filtration and fining are processes that have been used in winemaking for centuries (at least). Both procedures do the same thing – they clarify and stabilize the wine by removing contaminants, excess yeasts and bacteria so that the wine doesn’t go off or even re-ferment down the line. With finings, agents like bentonite clay are added to the wine, where they attract contaminants and fall to the bottom. Filtration involves passing the wine through very fine membranes to remove bugs and unwanted substances; filtration is, however, seen as more aggressive than fining.

If filtration improves the stability of the wine, why do so many people not do it or even dislike it? Well, filtration has coincided with the rise of natural and organic wine production and so many believe that filtration takes out the character and the subtler tastes. Drinkers looking for nuanced expressions of terroir and grape are turning to unfiltered.

What’s wrong with it?

Natural and unfiltered wine making isn’t like leaving it and forgetting about it for months; it demands a lot of attention and monitoring, even if the wine isn’t touched or moved much. However, critics of unfiltered wines claim that the “character” and “expression” are actually faults that could have been remedied by fining or filtering.

Unfiltered wine isn’t always dodgy or poor quality, though; far from it. Wine producers have a much deeper understanding of the biological processes that go on in fermentation and aging and so can control and monitor it more. For example, with unfiltered wines that are aged in oak barrels, the sediments fall to the bottom over time, which means the wines can be racked (separated from the solid sediments).

To return to the original question of whether unfiltered wine is better, though, the answer seems to be sometimes yes, sometimes no. This is probably why the debate will go on for quite some time. It’s probably the case that people will be advised to look at the producer and its processes before deciding on a wine-by-wine basis.