One of the wines that we offer for tasting has a reputation of having sediment on the cork and in the bottle. The reaction I get from some people are distinct disgust and you will be surprised on how many people actually think I’m secretly trying to kill them by adding glass particles in their wine… Upon opening the wine I will go through my normal explanation as to why there are reddish crystals stuck in the opening of the bottle or the cork:
“Yes the wine is currently throwing sediment, but do not worry, there is nothing wrong with it. Actually it’s a tell-tale-sign of a superior wine, because the acid lowers the PH in the wine to such a level that many of the bacteria that can spoil the wine will not survive. Its more natural because the wine was not overly stabilised and filtered, which gives you a more naturally flavoured wine” And then I pass out due to a lack of oxygen.
Thus I have decided; taking the best interest of my clients at heart, to open a bottle, finish it and get to the bottom of this well known culprit.
If you want to be technical, the crystals that are formed are due to a natural division of the tannis, the colour pigments and bitartrates (that’s acid, bru) due to age or cold temperatures.
The crystals are called tartrates, and the acids for these tartrates are found naturally within many fruits like bananas, grapes (no surprise there) and are antioxidants. Bitartrates are also known as Potassium Tartrate and are harmless. HARMLESS PEOPLE!
In grapes, these acids are produced naturally and have a higher concentration in cooler growing areas as opposed to warmer areas that would have higher sugars but lower acids. Many wine makers would put their wines through cold stabilisation and chill the wine to such an extent that these acids will crystallise and will form either on the inside of the tank, or settle to the bottom. Thus creating a more aesthetically pleasing wine for bottling. The problem with putting your wines through such a harsh method of stabilisation is that you also rob the wine from it’s finer, more subtle characteristics. If you are faced with a wine that has particularly high amounts of tartrate crystals, don’t despair because you have just opened a wine of high quality. When opened, let most of the tartrates settle to the bottom of the bottle and then slowly decant the wine over into a decanter or similar vessel. Let the wine breathe and serve.
There is good reason why these crystals are called Wine Diamonds.