Waiter...There's a Crystal in My Wine!

I got an email last night from a reader that I thought would be to share.

After all, as LENNDEVOURS evolves...I'm hoping to add more educational content.

In his email, he asked:

"Lenn, I just had a bottle of Castello De Broghese's 2004 Novello. Delicious and paired well with a leg of lamb I had. Anyhow, in the last glass, I noticed there were crystals of I what am hoping sugar on the bottom. Is this common with this wine?

It has to be sugar crystals, because when I washed them with water, they retained their color, I got scared for a moment that ground glass found its way into my bottle."

Don't worry my wine-loving friend. These crystals are not ground glass...and they aren't even sugar either. Keep washing them with water and you'll notice that they don't dissolve. Sugar would.

What are they then? They are potassium-bitartrate crystals.

And they aren't a flaw in the wine at all. They don't affect the flavor or color in the least...and they won't hurt you either.

I'm not the Alton Brown of wine, so I won't get too deep into the science at play here, but here's a brief run-down:

As grapes grow, they pick up minerals from the soil, including potassium. And, the riper the grapes get, the higher their levels of tartaric acid. So, when certain wine is cooled, either sitting in a cold warehouse or just before serving (CdB's Novello is a light, low-to-no tannin wine so it can take a chill) the potassium and the tartaric acid get together to form these potassium-bitartrate crystals.

I've seen them quite often on the wet end of a cork but you'll also see them on the bottom of the bottle.

For those of you unfamiliar with it, Novello is a red wine, made in a style similar to Beaujolais Noveau, but these crystals (sometimes called wine stones) can happen in both red and white wines.

If you see them in a bottle of white wine, do not decant the wine. I never decant whites because I think a lot of white wines lose aroma and character with air contact. Ever notice that white wine glasses are narrower and lead to less surface area? Just pour carefully as you get to the last glass or so.

For reds, you can either pour carefully or decant. Nine out of ten times I'd probably just pour carefully, especially with a gulping wine like Novello.

Fun Fact: Castello di Borghese has the oldest vines on Long Island (planted in 1973). They were planted as Hargrave Vineyard...and the Hargraves sold to Marco Borghese in the 1990s.

Comments

[Kevin]

WOW, Who knew that my little inqiry email would be come an informative post.

Thanks Lenn.

The Novello is certainly a buy again on the next trip wine, it was absolutely delicious.

[Wine & Vine BC]

Most of the time we take those bothersome crystals out of the picture by chilling the wine for a period of time. Even the reds.
Sometimes the wine is altered after the chillin' and the tartrate solubility is altered and more shakes out after packaging.
The chilling can take weeks to accomplish what needs to be done. But we have a fast track: Chill subject wine to -1C. Mix in Cream of Tartar (about 4 grams/L). This "seeds" the wine and the tartrates almost instantly precipatate. After a few days the wine can be racked or filtered off the creamy bottoms. Creamy Bottoms? Isn't that a punchline for an old joke?

[Emily]

Hi Lenn-
In Austria, they call 'em Weinstein, or, "wine stones", and many even consider them to be a sign of a high-quality wine (which might be why I have also heard them referred to as "wine diamonds".) When we asked one of the winemakers whose wine we import, Hans Gsellmann, he told us: “Part of the grapes acid are tartrates, aka salt. As the wine ripens these tartaric acid crystals fall out. It’s a natural process a wine will go through on its path to the peak in 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.”