Newly fermented wine is supersaturated with natural potassium bitartrate (cream of tartar). If not removed from the wine, chilling the wine will result in the precipitation of the tartrates into glass-like crystals commonly referred to as “wine crystals.”
In order to insure the wine’s clean and clear appearance for the consumer, these potential sediments are removed from the young wine by one of three methods:
1. Ion Exchange – a sophisticated chemical process.
2. Seeding – Adding certain chemicals to the wine then chilling (25-30 degrees F) for one to two days.
3. Chilling – The wine is chilled to 25-35 degrees F for three to five weeks.
It should be pointed out that these crystals are harmless, tasteless and do not detract from the flavor of a wine. In German wines their presence is a sign of quality.