What are tartrates?
Sometimes you will find some tartrate crystals in a bottle of wine, particularly stuck to the cork or settled to the bottom of the bottle. These crystals are comprised of potassium bitartrate, also known as cream of tartar in your kitchen, and are completely harmless. During the winemaking process, a wine is often cold-stabilized to try and remove these crystals; this is accomplished by holding the wine at a very cold temperature for a length of time, usually a few weeks. However, the removal of tartrates is a solubility issue as well as a temperature issue and can take a long time. Therefore, after a wine is bottled and held for a time, more tartrate crystals may precipitate out of the wine and show up in your glass. But now you know that they are no big deal and you can impress your friends at dinner parties with your knowledge of potassium bitartrate!
