Have you noticed white crystals around the cork or at the bottom of the bottle when you open your wine? These are called tartaric crystals, commonly referred to as “wine diamonds.” Wine diamonds are an indicator that the grapes ripened for a long time, and that the winemaker fermented the wine slowly and with great care. Both are important precursors to crafting high-quality wines.
Grapes naturally contain several organic acids including tartaric acid. They also contain potassium and calcium ions, which form salts with the organic acids. These salts can precipitate out of the wine to form a material called potassium (calcium) bitartrate or “wine diamonds.”
Many wines undergo a cold stabilization process, which is when a wine is cooled down before it is bottled so that these white flakes “fall out” and can be separated from the wine. But, cold stabilization influences a wine’s balance and taste. (KingFrosch does not do that). As some winemakers put it, the wine is actually being ripped apart, and the rapid cooling changes the wine’s colloidal structure.
“It’s a natural process a wine will go through on its path to the peak of its development. When you see these flakes at the bottom of the bottle or on the cork, you can be almost certain that you are opening the wine at the right time. You should consider yourself lucky.”
Wine aficionados in the Old World are known to seek out the bottles with wine diamonds as a sign of quality: it shows that the wine has not been robbed of its structure through unnatural chilling, and it is a sign of a well-matured wine.
So, if you find wine diamonds in your next bottle, consider yourself rich in both quality and experience!