Imagine you have just sat down to a beautiful dinner. You pull the cork from your bottle of Chardonnay and it looks like there are shards of glass on the cork. You pour the wine and a few more pieces fall into your glass... or worse, you don't notice anything until you've taken a sip! This may be alarming, but rest assured, these are not pieces of glass in your wine. Before you dump that delicious wine down the drain, let us give you a quick education in tartrate crystals.
More affectionately known as "Wine Diamonds"
among wine professionals, tartrate crystals
are completely harmless and will not affect the flavor of the wine. Tartaric acid
is the primary acid found in wine that promotes balance and lends to an elegant mouthfeel. When this acid binds with potassium in a low temperature (below 40
°F), tartrate crystals are formed. (These formations are actually Cream of Tartar, a common household baking item, in its solid form.) Tartrates may be removed through cold stabilization
, a part of the winemaking process where the tank of wine is chilled down to approximately 32°F for a period of time before bottling, to ensure that crystals do not form later on. Cold stabilization must be managed carefully, as colder temperatures increase a wines’ ability to absorb oxygen, which leads to premature aging. So while tartrates may be reduced, cold stabilization may never fully eliminate them. Additionally, tartrate crystals are more commonly found in white wines versus red wines because the tartaric acid levels in white wines are higher. (You're also probably putting white wines, not red wines, in your kitchen refrigerator where temperatures are colder.)
The best way to minimize the presence of Wine Diamonds in your white wines is to store bottles at 55-60°F and chill them down to 46-48°F prior to serving. Do not store white wines in your refrigerator, as the standard 35°F temperature is far too cold and can encourage the formation of Wine Diamonds. These crystals will dissolve in warm water, and are completely harmless and tasteless if ingested.
The next time you see Wine Diamonds in your glass, don't fret, and don't pour out that perfectly good bottle of wine. Your wine could be a real "diamond" in the rough!