Picture this. You bring home a nice bottle of white wine, chill it down to just the right temperature, pour it in front of your friends and what happens? Something that looks like tiny shards of glass can be seen floating in your wine.
Problem? Well, no, not really.
What you’re seeing are tartrates, which are formed when the tartaric acid (which occurs naturally in grapes, bananas, and tamarinds) is combined with potassium (which also occurs naturally in wine and is in fact one of wine’s health benefits) under cold temperatures.
The first thing to know is that these tartrate crystals are completely harmless and quite natural. They are also tasteless and odorless.
The second thing to know is that they are often a sign of higher quality wine.
Tartrates occur quite naturally during the fermentation process. Some wineries choose to use the Cold Stabilization process – a process that actually does nothing to improve the aroma or the flavor of the wine, but does filter out the tartrate crystals and turns the wine into something clear, filtered, processed, and de-sedimented. Unfortunately, many experts feel that this can filter out a little of the flavor.
In Europe, tartrate crystals are generally accepted, and indeed appreciated, because they show that the wine is one of quality and is made naturally. In Germany they call them “weinsteins” or “wine stones.” You might want to think of them as “wine diamonds.” They act as an anti-oxidant, they maintain the chemical stability of the wine, and in a pulverized form they are what you buy at the supermarket as Cream of Tartar.
Tartrates can also appear in red wine, but because they are colored by the wine, most people accept them as sediment – something else which often shows the quality of the wine.
So what do you do if you find tartrate crystals in your wine? First of all, don’t worry. Next, stand the bottle upright for a while and let it settle. Then pour it carefully into a decanter (or if you don’t have a decanter pour it very carefully into your glass). Serve and enjoy. It’s a great bottle of wine!
–Bill Stobbs, Wine Supervisor, West Coast