Why does my wine have crystals in it?
Tartrate Crystals, affectionately known by industry professionals as
“wine diamonds,” are tiny, crystalline deposits that occur in wines
when potassium and tartaric acid, both naturally occurring products
of grapes, bind together to form a crystal. The crystals are the same as
Cream of Tartar which is used widely in baking to make cakes and souffles lighter and airy.
Tartrate crystals are a harmless, naturally occurring by-product of winemaking; they might taste a little sour if you try eating them. They typically collect on the cork or at the bottom of a wine bottle. If red wine is stored in good conditions at around 17-18 degrees Celsius, these crystals should not form. Generally, they will only appear in red wine if the wine is stored at cold temperatures below 10 degrees.
Tartrate crystals (wine diamonds) are a harmless occurrence, and if swallowed will cause no ill effect, (possibly a slight gritty taste on the tongue) and these ‘wine diamonds’ do not subtract or add any negative characters or flavours to a wine, as they are naturally occurring in grapes.
The Crystals may not look pretty in your wine glass, but don’t let it slow you down! The wine is still perfectly safe to drink.