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Tartrates in your Wine Glass: Do They Matter?
Wednesday, May 14th, 2008 at 10:24:44 AM
by Josh F., Wine Enthusiast Companies
Have you ever taken a nice, white wine out of your cellar and as you reached the bottom of the bottle, noticed there were crystals floating in it? These are tartrate crystals. They are formed when the tartaric acid in your wine combines with the potassium (also found naturally in wine, another one of wine’s many health benefits) under very cold temperature conditions forming the salt, potassium bitartrate. If you’ve ever used cream of tartar in cooking or baking, it is the same substance pulverized into a powder. In fact, these crystals scrapped off of wine barrels are the source for the cream of tartar you buy in the supermarket. Tartrates can be found in red wines as well, but they are more often found mingling with the sediment, and are normally decanted out.


Wineries can and do add a step in processing called cold stabilization. Here, they chill the wine down to near freezing, causing the tartrates to precipitate out. Then they filter the wine to eliminate them.

The higher quality a wine is, the more likely it is to have tartrates. This is because good wines are not cold stabilized, filtered or over processed, in order to preserve the intricacies and subtle character of the wine.

If you’ve ever seen these tartrates, you may have wondered what to do about them. Well, one thing you can do is absolutely nothing. Tartrates are completely tasteless, odorless and harmless, so there’s nothing you really have to do. However, if you don’t like having these little crystals floating at the bottom of your wine glass you can simply decant your white wine as you would an older red using a funnel with a screen.
 
You're quite right about the heat Wolf. You can still buy wines with diamonds in them. Think about it, if they fell out of the wine due to cold, then surely they should go back when the wine warmed up.
Most people wouldn't buy a bottle if they saw Diamonds in the bottom. That's why most wines are filtered.

Regards to all, Winemanden. :h
 
I don't think the crystal will go back into suspension if the wine is warmed back up. There were several posts about this very subject earlier in this thread.

I think one problem is concerning folks who don't know about these crystals; after all, they can appear very much like glass crystals.

When I give a bottle of my wine to a friend, I don't like having to explain that they might see what looks like glass in the bottom of the bottle, but not to worry about it. I just go ahead and do a CS, which of course doesn't guarantee there won't be further fallout in the bottle...

Other than that, the presence of the crystal doesn't bother me at all.

In some circles, in Europe especially, a really good wine is sort of supposed to have some sediment and crystals in the bottom of the bottle. Go figure.
 
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Yeah - I agree - i just do a CS - and don't worry about it. That way i know the bottles i give away won't have anything in the bottle but wine.

But again - I am a perfectionist - bottles i give away are crystal clear, been CS, filtered, etc..
 
Yeah - I agree - i just do a CS - and don't worry about it. That way i know the bottles i give away won't have anything in the bottle but wine.

But again - I am a perfectionist - bottles i give away are crystal clear, been CS, filtered, etc..

I guess I should be filtering, also. I acquired a gravity filter as a part of some equipment I bought from a friend. I just have never used it.
 
To day I placed a glass gallon jug into the freezer. I will probably leave it in there for a month. Now I'm beginning to worry about the glass when I remove it from the freezer. Will it break? Any ideas or should I remove it to the fridge before it freezes. Has anyone done it with glass? :a1
 
Ive never used the freezer myself, I use my fridge for longer periods or my cellar. I have 6 gallons of Chard in the cellar right now with a nice layer of diamonds in there that Ill probably filter next weekend and bottle.
 
I'd be careful that it don't freeze and crack. Put it in a snow bank or spare fridge.
 
To day I placed a glass gallon jug into the freezer. I will probably leave it in there for a month. Now I'm beginning to worry about the glass when I remove it from the freezer. Will it break? Any ideas or should I remove it to the fridge before it freezes. Has anyone done it with glass? :a1

Richard I now have a thermostat on my freezer and can't get it to go below 27*. To monitor the temp I bought a cheap indoor/out door remote thermometer from Wally World. I pace a few 1x2" strips on the bottom of the freezer to sit the bottles on. I have also done glass gallon jugs and 750ml bottles. I have never left them in longer than two weeks. Before I had control of the temp and the freezer was in the single digits I only left the wine in 3-7 days.
Ideally tip your jug on the 1x2 in the freezer. Carfully remove and set on your bench when ready still tilted on a 1x2 to keep the crystals on one side if possible. Use extreme caution not to bank into other glass while chilled. Rack off when wine is nearly room temperature.
 
Filtering the wine does not guarantee there will be no further fallout of crystals. Even with cold stabilization, you could get further fallout. I have filtered with a 1 micron filter and have still gotten some crystals and it was some of the best white wine I have had. Don't worry too much about it.
 
Grapeman is absolutely right. Filtering will not stop fallout of crystals. I also filter with a 1 micron filter and and had plenty of fallout. Thats the reason I cold stabilize all the time now.
 
I have an old fridge that I can only get down to the low 40's. Is that low enough to cold stabilize? Is there a level you have to get to?
 
Does cold stabilizing actually improve the wine, or is it merely a cosmetic effect?

Assuming your wine is perfectly balanced in the first place, won't CS throw it out of balance? Has anyone done a Ph/Ta before and after test?

Just me being curious again.

Regards to all, Winemanden :h
 
Its mostly cosmetic. Under normal conditions you will see a small drop in TA and a small increase in pH due to the loss of some tartaric acid.

That said it is usually not enough that you can actually taste much difference. Your wine will still be balanced after CS if it was before.
 
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