Filtered or Unfiltered

It's a hot trend in 2021, but much like other trends, nobody seems to know why. More than ever before, at least in my memory, people are drinking unfiltered wine. In fact, based on my observations strolling near the wine area at my favorite big box store that happens to sell wine, people are seeking out unfiltered wine. I probably should have grabbed my handy dandy portable microphone that I always carry with me in case I need to interview someone (if you believe that, there is a bridge in Brooklyn I will sell you) and asked these people why they were looking for wine, but I just didn't have the foresight. So, just as you do, I have to guess.

What is unfiltered wine, anyway? I know, it's wine that's not filtered. So, I guess we need to know what filtered wine is.

We're probably all familiar, at least conceptually with the fermentation process. That's the one in which the grape juice turns into an alcoholic beverage. To look at such a wine, it looks quite cloudy; in the Old World, blind is the more common term.

To get rid of the cloudiness, the microbes and the particles of yeast are separated from the rest of the product or filtered. Sounds simple enough and frankly obvious enough to do this. In fact, wines typically go through two phases of filtration. The first one filters out the yeast and the second one removes those squirrelly little bacteria, at least most of them.

The message thus far is that if we don't filter the wine, it's going to be cloundy. But, people won't buy a cloudy wine nor should they. So, the alternative process that is used involves racking the wine. After fermentation, the wine settles and we let gravity do its thing. The heavy stuff goes to the bottom and the light stuff stays at the top. Once that happens, the wine is siphoned off from the lees in a process that we know as racking.

What we are left with in an unfiltered wine is more bacteria. Now, some bacteria are good and some are bad for us. I don't know which are which and I certainly can't look at a bottle of wine and tell you which bacteria are still in there. No matter your expertise, neither can you.

Left to their own devices though, those bacteria will stay in the wine and do what bacteria do. They might change flavors or react with other parts of the wine. They might cause the wine to turn or spoil earlier. 

To help to solve this problem, typically either or both of two techniques are used. The first is to treat or stabilize the wine with more sulfites, but we already know that sulfites have a bid stigma among wine consumers. The second possibility is to put the wine through malolactic fermentation. Long-time readers will recall that this is the process by which malic acid (that's pretty tart stuff) is converted to lactic acid (that's soft and creamy). Wines that have not gone through malolactic fermentation tend to retain more of their fruit flavor while wines that have gone through the process lose some fruit, but have that pleasant mouth feel.

After all that, should you drink filtered or unfiltered wine? Is there a reason that people are gravitating toward unfiltered? I suspect if feels more natural and natural is a trend in 2021. All that said, I bet you that if I pour you a wine, you can't tell me if it's filtered or unfiltered. If you can, it is likely true that you are a wine geek and the style of the wine is a giveaway.