Fining and filtration are conventional techniques of long standing, but that doesn’t mean we shouldn’t question their use. How do we rate time-honored tools against new technologies? In the spirit of “never eat anything you can’t pronounce,” should we use our own ignorance as a yardstick for health? If that worked, American natural wine buffs would surely be the healthiest demographic on Earth. That’s not entirely their fault, because in today’s Don’t Ask Don’t Tell world, no sane winemaker seeks to educate the outside world on interventionist practices.

But I will. Nobody ever accused me of excessive sanity, let alone coyness.

In my opinion, no novice or even connoisseur should try to second guess processing decisions of his chef or his winemaker. I advocate choosing your artisans well and delegating the details. But for readers who still imagine you can sort these things out on your own, here’s a summary of the issues.

Filtration, I reckon you can work out on your own. Whether filtration is bad for wine is a matter of open debate. In The Great Winemakers of California, Ridge Vineyards’ celebrated anti-tech winemaker Paul Draper, who explains that he declines to filter because eschewing the practice forces more care in the cellar, famously opined that filtration, properly done, does not harm wine. Though many winemakers share this view, I personally disagree. It’s an old book -- perhaps Paul does too these days.

There is a clear quality advantage to sterilization, the same as there is in cheesemaking: it removes the risk of undesirable microbial activity in the product after release. But the greatest cheeses are unpasteurized. In wine as well, sterilization removes both the downside and the upside. So if one chooses to avoid filtration, it is critical to allow microbial activity to come into balance before bottling. These things we understand.

Fining is a lot more obscure in both its goals and its tradeoffs, and I will confine myself to that aspect here.

So what is fining, anyway?

The prime directive in winemaking is that nothing is added but grapes, yeast and oak. We are allowed to add materials such as tartaric acid or malic acid because they are naturally occurring in grapes. Fining agents are allowed because they aren’t supposed to add anything to wine; they are adsorbents to which can take things out of the wine, because they have bind specific undesirables and entrain them out. You make a slurry in a bit of wine, mix it in, let it settle, and rack the clear wine off the fining sediment which has fallen to the bottom of the tank along with the bad stuff – say some excess tannin -- stuck to it.

To obtain U.S. government approval, fining agents are required to be completely insoluble and have been considered in the past to leave no residue. For this reason, their use does not require a label statement.

There are several kinds of fining agents. Chief among them are bentonite clay, PVPP, proteins, and carbon.

Substantially all white wines receive bentonite fining. Bentonite is a clay mined in Wyoming that has amazing affinity for protein. Some minimum quantity is routinely added to prevent cloudiness which can occur after filtration and bottling. Bentonite is considered utterly benign, is approved for organic and kosher winemaking, and is universally employed. Bentonite is never used on red wine because there is no need – red wine’s tannins precipitate any protein naturally.

Another fining agent routinely used on white wines is PVPP (poly vinyl poly pyrrolidone), a finely ground plastic similar to nylon. PVPP removes pinking precursors, nasty little skin extractives which can cause white wines, especially sauvignon blancs which have never seen oxygen, to turn pink after bottling. Again, PVPP is routinely used, entirely benign, and never used on red wines.

The words “Unfined, Unfiltered” are only found on red wines. The most common fining agents for reds are various proteins used for removing tannin to reduce harshness and bitterness. Tannin’s harshness is caused by its affinity for the proteins in saliva. When you put a big red wine into your mouth, its tannins strip the mucous coating from your palate and replace it with a sandpaper-like grainy astringency. Different types of tannin cause different effects, such as the location in the mouth where the rough sensation occurs and the fineness of the graininess. Very fine tannins are much more pleasant, and tannin on the top of the tongue improves with age (“hard” tannin) whereas grittiness under the tongue is a sign of deterioration (“dry” tannin).

Protein added to tank or barrel takes the place of salivary protein, combining with and removing unpleasant tannin prior to bottling. The four approved proteins are all animal products: albumin from egg whites, gelatin from beef tendon, casein from milk, and isinglass from the swim bladders of sturgeon fish. A fifth agent, blood, was made illegal in the Sixties in response to a scandal based on the absurd fear that red wines were being artificially colored with blood.

Consumer concerns about allergens have brought a completely new slant on fining. The U.S. government position on egg albumin, casein (milk protein), isinglass (fish protein) and gelatin (beef tendon) has been for the last seventy years that they leave no residue, and therefore, just like stainless steel or inert gas, can be in contact with wine because they don't add anything. Instead, they remove tannins to reduce harshness. These materials are considered insoluble in wine, and hadn't been regarded as a problem.

Now that we have heightened consumer awareness, we are scratching our heads and wondering if we have a problem after all. In this increasingly toxic world, sensitivity to allergens seems to be on the rise. My wife is terribly allergic to wheat, so I understand that very small amounts of an allergen can promote a reaction. But everybody who’s allergic to a given food isn’t necessarily reacting to the same specific allergen (for instance wheat gluten), and those that do react to it don’t share the same antibody recognition sites on that protein, nor are they sensitive to the same levels. There simply isn’t any way to set a standard as to what constitutes a safe level of residue. So we have no way to determine what is safe for any specific individual, and no way to do studies.

So it’s just possible that certain individuals could react to trace amounts of specific protein residues. Now if you think, as I do, that these questions are best addressed by avoiding wines which make use of these products, then one strategy is to restrict your consumption to, ahem, post-modern winemakers such as myself.

The reason is that animal agents for fining tannin are obsolete. There is no need for them. Tiny, carefully administered quantities of oxygen (micro-oxygenation), when used with skill can smooth these tannins without the flavor stripping of animal protein fining agents, thus rendering their use unnecessary and undesirable.

Postmodern winemaking seeks to eliminate red wine fining. Protein fining not only strips flavor, it also removes the tannin colloid structure from wine which is responsible for its aromatic integration and soulfulness. It is a product of the flawed solution chemistry scientific theories of the last century and it doesn’t work. It un-tunes wine and robs its core fruit expression and profundity. Fined wines are thinner, but they are often also harsher than the starting wine. Quoth Randall Grahm, “My mantra is ‘I will fear no tannin.’”

While we’re on the subject of allergens, articles such as the ridiculous alarmist tripe slung together by Corrie Brown of the LA Times (mercifully now unavailable on their site) have also pointed to the wheat paste occasionally used by coopers to repair barrels as a potential source of allergen. Since all wines are fined for protein either naturally or with bentonite, it seems unlikely that exposure of any significant level can occur, but I don’t want to seem cavalier. For those who are open to oak chips to provide extractives rather than new barrels, wheat paste exposure can be substantially reduced. Well-made chips provide identical flavors to the finest barrels at a fraction of the cost to the consumer, and they also reduce the rate at which 200-year-old French forests are cut down by a factor of four.

This is discussion alas barely scratches the surface. The Center for Panic in the Public Interest began in 1980 a serial campaign to alarm the public about wine. The allergen scare is their latest ploy. They really hope you won't study the issues at all. If the consideration of these complexities causes consumers to decide simply to walk away from wine, then they have found their mark. But the Wine Industry is far more regulated than most foods; do not imagine that the rest of your food supply is any safer!

Short answer is this: If you are concerned about eliminating animal products from your wines, seek out producers who use micro-oxygenation instead. If you are worried about wheat products or have environmental concerns, seek out producers who use oak chips instead of new barrels. The more consumers demand these changes, the more producers will disclose these details. For now, you have my wines at least, available at winesmithwines.com. We do NOT use additives, unless you want to count air.