To Filter or Not to Filter?

I know, I know. If you read my last post, I promised to go over the difference between red and white in this, my next blog. But I hope you’ll forgive my digression to a more apropos discussion of filtered versus unfiltered wines. (Alright, it’s really only more pertinent than delineating what makes a red a red and a white a white--besides their color--because it came up over the weekend when my friends and I split a bottle of Basignani’s Marisa. But as they say: timing is everything….)

The motivation for my digression began a little like this:

“Oh good, it’s unfiltered!”

What is he talking about? I made a noncommittal noise as my friend finished reading the label and passed me the bottle to uncork. While I used my winged, you’d-have-to-be-an-idiot-to-mess-this-up corkscrew (sorry to my roommate if she reads this, but I still don’t understand how she managed to push a cork into the bottle a couple of weeks ago), I vowed to look up the difference between unfiltered and filtered wine at the earliest possible opportunity. After all, of the three of us, I’m the one working at a winery. This, I thought, is something I should know.

That was Friday. My determination to understand this filtered versus unfiltered business was cemented the next evening (Saturday, for those of you without easy access to a calendar) when one of my friends finished the bottle and discovered sediment in the bottom of her glass:

“Umm, Ryn. What’s that?” She tapped a curious and slightly cautious finger against her glass, directing my attention to the small pool of red at the bottom.

“Sediment. It’s unfiltered.” I could tell she was impressed with my ability to put two and two together and get four (a special thanks to my other friend who’d noticed the UNFILTERED printed on the label, therefore enabling me to sound knowledgeable), but her question made me realize that observing a correlation between the word “unfiltered” and the presence of sediment in the bottle was really just the beginning.

Again, I thought, This is something I should know.

My first instinct, as a member of Generation-Y (or whatever you want to call us), was to Google. So I did. Though there are a lot of hits for “Filtered versus Unfiltered Wine,” none of them seemed particularly reliable (with the notable exception of eHow.com).

So, I harkened back to elementary school and the days before Internet research. Yes, that’s right, I opened a book! I got out my copy of Phillip Wagner’s Grapes into Wine and used the index (the INDEX!) to look up filtration. Though his discussion is perhaps a bit too in-depth for a blog post, I thought I’d give you the highlights of wine clarification: what it is and whether or not it matters to the average consumer.

Sediment in wine is natural, even unavoidable—small particles from the grapes and dead yeast cells are inevitably left behind. Sediment, to me, has a bit of a negative connotation (after all, we talk disparagingly about sediment making rivers and streams murky) so I feel compelled to point out that there is nothing inherently good or bad about sediment in wine. It just is. The particles found in wine include tannins, coloring phenols and proteins—all of which are natural and none of which are harmful if consumed.

Still, some consumers (especially within the past 50 years) have come to equate clarity with quality. To clarify wine, some winemakers use finings (an agent that bonds with the suspended particles in the wine, pulling them to the bottom) while others use filtration.

Filtration, according to Wagner, “is in a sense the reverse of fining. When a wine is fined a sort of veil of the fining material is drawn down through the wine, dragging all suspended matter with it. When a wine is filtered the veil, a porous wall or membrane, is fixed and the wine is forced through it, leaving the suspended material behind and emerging clear and bright” (189).

There are several advantages to filtration over fining, including: time (filtration is much quicker than fining), consistency, the lack of chemical reactions, and the simple fact that filtration can be implemented at any point in the winemaking process (190). Despite these advantages, however, some winemakers are reluctant to filter, as the process may change the quality of the wine’s flavor and aroma, not to mention its aging potential.

Here at Basignani, we prefer to leave our dry wines unfiltered. If you’re worried about sediment (as drinking the sediment itself doesn’t taste very good) you can decant the wine, then pour carefully to keep the sediment out of the wine glasses. (In other words, don’t pour like a college student and upend the bottle…wine is not always good to the last drop!) 

Wagner, Philip M. Grapes into Wine: A Guide to Winemaking in America. New York, NY: Knopf, 1986. Print.