No culture has more creative and fitting descriptors for wine than the German, at least as long as someone is around to translate. One example: Notice how wine behaves on the inside of a glass as you drink from it? Droplets form and slide down the walls in various thicknesses, lengths and shapes. Most of the wine world calls them "tears" or "legs." Germans, however, liken them aptly to "church windows" for the tall, narrow and arched frame of a shape they frequently take. Doesn't that speak more to the grandeur and nobility of wine than "tears" and "legs"?
I was reminded of the Germans and their "church windows" lately as I did a little research after finding tartrates in another bottle of wine, the second such incident within a week.
Tartrates, which can look like shards of white glass, or flakes of snow, or crystalline clumps of salt as they cling to the bottom of a cork or float languidly about the bottom of a bottle of wine, are apt to alarm wine drinkers. This is much less likely to happen today than in the past. Modern winemaking techniques like refrigeration and filtering pretty much eliminate the prospect of these tartrates from most wines, so they aren't seen as much today as they used to be.
Why I've seen them in two different wines within a week is a mystery, but I have a hunch some wnemakers could be reverting to a few older winemaking methods or shortcuts out of concern that high technology could be stripping wines of character as well as the occasional shower of tartrates. They may be willing to take the risk of tartrates to offer consumers a better wine.
And the risk is solely to the winemakers. Americans like their white wines pristine, without any cloudiness and certainly not with some substance floating in the bottle that looks like broken glass. The risk, then, is in the mareting of the wine, not its nature or quality. Tartrates generally settle to the bottom of bottle or glass, or they could be left behind by decanting the wine as soon as it is opened.
Even if they were ingested by consumers, they'd do no harm. They're fragile, they're a natural byproduct of winemaking and they're more a visual nuisance - or a sign of Old World wine craftsmanship - than any indication that something is wrong with the wine. Both wines we sampled with the tartrates, in fact, were exquisite.
Tartrates, also called potassium bitartrate or potassium salts, are simply an offshoot of tartaric acid, the principal acid in grapes and wine. Because tartaric acid is only partially soluble in alcoholic solutions, some deposits may form. Chilling and filtering of the wine customarily gets rid of them, but some winemakers could be cutting back on those techniques to better retain other attributes. (How harmless are tartrates? They're actually beneficial. Deposits that form on wine casks are scraped off, preserved and purified as cream of tartar, a common ingredient in baking.)
Wines from cooler grape-growing areas tend to have more tartrates than wines from warm regions, which helps explain why they don't show up often in California wines. In contrast, Germany is a cool grape-growing area, and tartrates in German wines are more common. There, the German penchant for fitting and even poetic wine descriptions again comes into play. They call tartrates "weinstin," or "wine stones." What a great term, not only for describing how they look but for reinforcing the link between the wine in the glass and the grapes in often stony vineyards.