Wine grapes consist of three main acids which include malic acid, citric acid and tartaric acid. Tartaric acid is very susceptible to temperature fluctuations. With these dropping temperatures it is easy to forget that bottle of wine in your freezing garage or store it in the fridge overnight. If the wine is chilled down too far, tartaric acid will actually solidify creating tartrates also known as wine diamonds.
Wine diamonds are naturally occurring particles that form in the wine during the ageing process or in the bottle if subjected to cold temperatures. They resemble crystallized sugar granules or crystal shards that appear on the bottom of the cork or settle at the bottom of the bottle.
The good news is, tartrates are harmless and more likely to appear in higher quality bottles of wine.
Although wine drinkers typically don't like the appearance of wine diamonds, they have no negative affect on the quality of the wine. Wine diamonds are harmless, tasteless and a natural process of the winemaking process. In fact, the presence of wine diamonds is viewed by many winemakers and sommeliers as a good sign, because it indicates that the wine was not over processed.
- Just prior to serving, wine should be chilled down o 45 to 48°F
- Wine shouldn't be stored in the refrigerator overnight
If wine diamonds still appear in your wine, you will likely want to decant your wine or use the small screen from your aerator to remove the crystals as they can be gritty. But remember they have occurred naturally, are nontoxic, and they help to preserve your wine.