not drinking poison in paris: the f word: the curse of filtration

27 April 2016

the f word: the curse of filtration

A kieselguhr filtration system.

I love natural wine. But I understand why the phrase "natural wine" and the sulfur discussion it entails can sometimes infuriate even its own supporters. In natural wine circles, the wine conversation has become so fixated on sulfur that other, equally fundamental questions are often getting overlooked. I refer mainly to the F-word: filtration.

I've been perplexed to see journalists and sommeliers I respect embracing filtered natural wines. And I was recently disappointed when one of my favorite wine writers, New York Times critic Eric Asimov, in his recent blind tasting of 2014 Morgon and Fleurie, duly quoted Kermit Lynch - the original champion of unfiltered wines - before awarding the two highest scores to plainly filtered wines.

To be fair, blind tastings are tough.* Beaujolais, and gamay overall, begins with a reputation for lightness, which might cause some tasters to presume a filtered wine is naturally light. But one of the more noble challenges of wine appreciation lies in preserving one's palate from habituation to technological shortcuts in vinification. This includes filtration, no less than sulfur overdoses or lab-cultured yeasts. In each instance, the potential quality of a wine is being sacrificed for the sake of a regularity more amenable to industrial distribution norms. The fact is that Kermit's 1980's crusade against wine filtration is still relevant today - particularly with regards to gamay, which seems to lose more from filtration than many other red varieties. Filtration of gamay is stylistically determinative: once you become attuned to it in a wine, it's as obvious as the difference between the burnish of real wood and the sheen of a plastic substitute.

Before continuing, I should mention I am not a winemaker, and my research on the subject of filtration is theory, not practice, unless one counts tasting. I have never had to stake my or my family's livelihood on a decision to refrain from filtering, which often requires a winemaker to cultivate better, more quality-oriented professional clientele. I also do not sell wine for a living, so I'm spared the chore of explaining the innocuousness of tartrate deposits day in, day out, for decades at a stretch, a burden that has been known to influence tasters. (Rare is the restaurateur or retailer who doesn't possess some innate fondness for easy wines that sell themselves with no explanation required.)

Anyway, here is what I believe at the moment about filtration of Beaujolais, and why.

Wine Type Counts.

I have hunches, but I can't necessarily speak of the organoleptic effects of filtration in other regions with different wine styles and grape varieties. The disagreeable effects of filtration could well vary according to region and wine type.

For example, the celebrated Rhône winemaker Alain Graillot has since 2013 been making a bit of Beaujolais tout court, Fleurie, and Saint Amour in a cellar in Tournus. The labels are excellent and the production standards immaculate. From barrel the wines taste splendid. From bottle, all I can taste is an absence resulting from kieselguhr filtration.

When I mentioned it, Graillot replied firmly that he believes in a little filtration for all his wines. Far be it from me to tell him to change his successful Crozes-Hermitages, a wine that, to my palate, doesn't seem to suffer as much from the filtration it undergoes. Yet his Beaujolais is perceptibly losing something in filtration. What's ironic is his Beaujolais wines see rather long elevage for the region - 11 or 12 months - and theoretically should have deposited most sediment by then.

Method Is Not That Important.

Four general methods of filtration are in current use for filtration before bottling:

1. Kieselguhr or Diatomaceous Earth Filtration
2. Tangential or Cross-Flow Filtration
3. Cartridge or Membrane Filtration
4. Plate or Pad Filtration

Each system of filtration has its own advantages and inconveniences. Kieselguhr is the most common in Beaujolais and seemingly the most adaptable. Tangential filtration is more costly to install and operate, limiting it to larger domaines. Membrane filtration incurs a greater loss of polysaccharides in the finished wine than some other forms of filtration. Plate filtration is prone to leakage if not operated correctly.

Winemakers who prefer a given system will invariably insist, with some justification, that successful use of it depends on mastering the complexities of process, and / or choosing precisely the right hardware.

I'd argue that none of this really matters. They're all bad methods for making great Beaujolais.

Filtered Beaujolais comports itself differently on the palate. It is more ephemeral, less impactful. In discussing the difference between young Fleurie winemaker Yohan Lardy's unfiltered old-vine Moulin-à-Vent "Les Michelons" and his other, filtered wines, Lardy hit upon the best word: "Granularité."

When young, filtered Beaujolais lacks the unifying grain of an unfiltered wine, with the result that the elements of the palate are incoherent. Tannins, acid, and fruit arrive separately, without synchronicity. With bottle age these elements often reunite sufficiently, but the wine usually remains somehow developmentally stunted, condemned to the minor leagues. And it sadly goes without saying that very few consumers age Beaujolais.

French oenologist M. Serrano concluded in his 1998 article Physical Treatments of Musts and Wines: "All filtrations have an effect on the chemical composition and the organoleptic characteristics of wine." Winemakers who systematically and totally filter their wines before bottling are making a compromise with industrial distribution norms and consumer inexperience. The reality is that many other winemakers exist who produce consistent, profound wines at all price points without excessive filtration. It's possible, and preferable, to do without it.

One Problem, Many Solutions.

Winemakers filter their wines for three principle reasons, only one of which is valid. The invalid reasons: because consumers mistakenly fear deposits in their wine, and because consumers prefer artificially snazzy limpidity. It is the job of sincere retailers, journalists, importers, and sommeliers to explain that wine deposits are harmless. I also believe it is our responsibility to promote appreciation of wines in their natural state, before colour correction. Colour-corrected wines are like pornography: eye-catching, but prone to encourage unrealistic expectations. It is healthier to appreciate the real thing.

Limpid wines can demonstrably be achieved without filtration. The more valid reason to filter is for fear of unpleasant aromas developing from bacteria and lees suspended in the wine. Sulfur addition can also combat this. In modest quantities I find it preferable to filtration. The different between a Beaujolais that has seen zero sulfur and one that has seen 1g/HL at bottling is very difficult to ascertain in tasting. Whereas Beaujolais that has been totally filtered is immediately identifiable to experienced tasters.

In my peregrinations around Beaujolais I like sharing the methods various ideologically-diverse winemakers use to avoid filtration. You'd be surprised by how many winemakers are unaware of their neighbors' habits, having never dared to ask.

Morgon's Jean-Marc Burgaud, for example, filters his spring bottlings (Beaujolais-Villages and Régnié) with kieselguhr. He bottles his Morgon Côte du Py later in the year, around June, because he feels that by then the wine has had enough time to clarify during elevage. Céline Hirsch in Chénas follows the same laudable reasoning. While I'd prefer these winemakers filter nothing at all, I'm still happy they choose non-filtration for their best cuvées.

At Domaine Lapierre and chez Christophe Pacalet, only the final fifth or so of each barrel is filtered. Afterwards that part is reassembled with the rest, with the result that the filtered minority of wine is essentially imperceptible.

Jean-Louis Dutraive in Fleurie reassembles the very bottom of his barrels into one barrel, which he then serves to his harvesters during the harvest. (Or, in the case of his "Vieilles Vignes," he drink it himself during harvest.) Yvon Métras does essentially the same. In both cases, the bottom-of-the-barrel wines remain magnificent.

Wording Matters.

I was tasting with young Blacé winemaker Sylvère Trichard recently and greatly enjoyed his 2015 Beaujolais tout court. For me it's the first year his wine has been as spiffing as his labels. Out of curiosity, I asked if he'd ever decided to filter his wines.

"Oh, these," he said, "They're all filtered."
"You're kidding. Filtered completely?"
"Oh no! Just the last thirty percent of the barrels."
"Ah!" I said, relieved. "Then say it differently!"

I had a similar interaction with Christophe Pacalet, although he may have just been teasing me. Filtration is a complex subject and most winemakers prefer to gloss over it and speak of other things. As an unfortunate result, winemakers who filter an inconsequential part of their wine often give the same response as winemakers who filter the entirety of their wine. It's important to ask follow-up questions.

History is Written by the Weeners.

In the 5th edition of his book Connaissance et Travail du Vin, the celebrated oenologist Emile Peynaud includes the following quote as evidence for the long historical validity of wine filtration:

The filtration of wines is a relatively modern practice but one which takes on a greater importance each day due to changes that are occurring in the conditions of transport of wine to consumers." - L. Degrully, Professor at the National School of Agriculture, Montpelier - Feb. 7th, 1904

This somewhat contradicts the 2nd edition of the same book (1981), in which Peynaud writes: "The generalisation of filtration of wines dates from thirty or forty years ago."

The first quote indicates that wine norms began to change with the advent of railroads. The second quote indicates that wine norms changed again in the wake of WWII, when supermarkets began to make substantial inroads in the wine market. In both of his book's editions, Peynaud intends to convince a reader of the essentiality of wine filtration. Yet such a conclusion is based upon the assumption that wine's encounter with the technology that has facilitated its global export has been salutary. Does anyone think this about, say, factory-farmed chickens? Or any agricultural product, for that matter.

Peynaud's thinking is a product of his time and his profession. Oenologists are paid - often by large companies - to ensure wines be stable and profitable. The greatest profits, then as today, are found in mass distribution models that rely on an uninformed clientele. This is precisely the distribution model that Beaujolais must rise above if its winemakers are ever to ask prices proportionate to the work required to produce great wine.

The good news is, wine norms can and should change again in the internet era. Wine information is available to consumers on a heretofore unimaginable scale. The wine industry is far from finished adjusting. In theory, it should be easier than ever to spread the message that taking nothing out of wine is just as important as adding nothing to wine.