Naturally made and un-stabilized wines develop crystals, which generally precipitate to the bottom of the bottle or attach themselves on the cork or the closure of the bottle. Sometimes referred to as “Wine Diamonds” they are indicative of good quality. Although crystals are bitter, they are harmless and do not affect the flavour of the wine in any way.
When grapes are de-stemmed and the free-run juice is obtained, the must naturally starts to ferment. The yeasts are on the skin of the grapes. When yeasts discover sugar in the must and oxygen, they start converting the sugar into alcohol and carbon dioxide. The must contains potassium from the soil, and tartaric acid, a natural component in ripe grapes.
During the fermentation the alcohol content increases gradually and potassium is combined with the bitartrate of the tartaric acid, thus forming potassium bitartrate in liquid form. (The powdered form of this is known as cream of tartar and used in baking.)
Alcohol induces the salt of tartaric acid to harden and most of the tartaric acid in insoluble form precipitates to the bottom of the fermentation tank or container, either shortly before, or after the fermentation stops.
When the newly made wine is cooled, more tartaric acid in insoluble form precipitates to the bottom of the tank. During bottling the wine is channelled through stabilizers. They consist of cooling pipes capable of dropping the temperature to – 4 C, which turns insoluble tartaric acid to crystals. Crystals are filtered thus making the wine brilliant. Occasionally some of the wines exposed to temperatures which are lower than the temperature by which the tartaric acids were removed, may attach themselves to the cork and precipitate to the bottom of the bottle.
Tartaric acid can be totally removed, but this process deprives the wine of some congeners (taste imparting particles).
Consider yourself fortunate if you obtain a wine which contains wine crystals or diamonds.
Simply remove the tartaric acid by either decanting the wine or separating the sediment from the wine. If it was clear at the time of bottling it will be crystal clear.
If wines enclosed with natural or synthetic cork are correctly stored, i.e. laying on their side, the tartaric acid particles will adhere to the cork. In the case of screw capped bottles tartaric acid will precipitate to the bottom of the bottle. Simply wipe the inside of the bottleneck and pour the wine.
Although both red and white wines contain insoluble tartaric acid, one more frequently finds crystals in sweet white wines, as they are stabilized at lower temperatures than dry whites.
Wine crystals or wine diamonds are indicative of quality and never impart an unpleasant taste.
To your good health!
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diseño de logotipo
April 21st, 2009 at 22:57
So good to know! i had been looking for “rotten wine” in google thinking there was something wrong with two of my bottles!! thanks for existing!!
Furniture Online
April 21st, 2009 at 23:10
hmmm… i always thought the crystals were a sign of a wine gone bad (that’s why you’re supposed to feel the end of the cork during the corking process). regardless, this is good to know!
Martin
April 22nd, 2009 at 00:29
Nice post.
Will look for them next time I open a bottle.
Martins last blog post..Misel št. 7
Morten Pedersen
April 22nd, 2009 at 14:39
We are all learning something new every day!
Anti Aging
April 26th, 2009 at 22:19
The crystals are found very rare and if you find the cystals it´s often in white wine. So I am drinking the red wine
Anti Agings last blog post..Vacuum pump
Morten Pedersen
April 30th, 2009 at 09:44
I’m drinking red too……
Laura
July 12th, 2009 at 17:18
Just stumbled across this post, and I really like it.
It’s great information and I’ll keep it in mind.
.-= Laura´s last blog ..Hunting Games =-.
Michael
July 17th, 2009 at 02:14
Interesting and informative article.
One can also find sediment at the bottom of the wine, particularly old wine.
Really old wine is usually decanted first. The wine is brought to room temperature and then slowly poured into a decanter or bottle leabing the ‘lees’ or sediment in the original bottle.
Dave Metz
July 20th, 2009 at 04:17
Interesting article. I wonder how the writier feels about screw tops as a replacement for the endearing corks. I found it very difficult to make the shift from cork to screw caps because it diminished the overall experience when opening the bottle.
.-= Dave Metz´s last blog ..Planted Tropical Aquariums =-.
Max Gates
July 27th, 2009 at 07:13
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.”
Some people fears such wine could cause health problems but They are of no health concern, although for some like my wife they are unpleasant if taken into the mouth, particularly if large when they may be mistaken for shards of glass.
Lisa
October 4th, 2009 at 04:46
Wow, I’ve never heard of or seen “wine crystals” before – Guess that means I’ve been drinking low-quality wine? We don’t really have any real dedicated wine shops where I live so all I get to drink on a regular basis is the stuff they sell in the grocery store like Arbor Mist, blech… No wine crystals in that stuff. Probably not any actual wine either…
.-= Lisa´s last blog ..Brewing My Own Beer! =-.
Morten Pedersen
October 4th, 2009 at 12:36
Thanks for the inputs, it has been interesting reading.
Frases de Bêbados
March 23rd, 2010 at 15:19
I really enjoyed this article, is a great informative read.
.-= Frases de Bêbados´s last blog ..Frases de Bêbados Engraçadas =-.
Aiping Wang
April 25th, 2010 at 12:50
The Gold Coast is a place for fun and unlimited excitement, which is perhaps why it is frequented by tourists from all over the world.
Aiping Wang
April 25th, 2010 at 12:51
One activity you will want to try out is the Classy Wine Tour, where you get to visit several wineries and observe how this delicious brew is prepared. You will get to walk through the vineyards, watch the crushing and storage and then eventually taste a few of the best wines of the world.
Aiping Wang
May 12th, 2010 at 12:13
Over time there has been a long tradition of growing vineyards in areas like the Napa Valley in California. Actually going back in history the first vineyard was planted by a Franciscan missionary in the year 1769.
Bernard Brady
June 17th, 2010 at 19:20
You sure do learn something new every day. I am thoroughly enjoying your blog, and highly recommend it to anybody who has an interest in learning about what makes wine what it is. It really is a fascinating science, with a liberal dollop of magic thrown into the mix.
I never associated wine crystals with good quality wine, but now I know and can simply not wait for the dining out moment when I can suitably impress my fellow diners. Bon appetit!
CAO
June 27th, 2010 at 00:53
Beautiful in Califronia, opened some wine and thought “oh no, what are these crystals?” looked it up & drank it down. Thx for sharing the knowledge! Topa Skal to all =D~