Comments on: Liquid Crystals

By: dan

dan — Tue, 16 Sep 2008 02:25:49 +0000

It was okay, but not great. It seemed very heavy, almost a touch viscous, for a Torrontés – even before noting the crystals I’d thought that it somehow seemed… doctored, or as if perhaps it wasn’t pure Torrontés and some much weightier grape had been blended in.

By: Ken Sternberg

Ken Sternberg — Tue, 16 Sep 2008 00:44:36 +0000

So how was the wine?

By: dan

dan — Mon, 15 Sep 2008 23:20:29 +0000

My first thought too was copper, just based on the blue-green color, but a little online and book research shows that copper precipitates from wine in a rust-red color. Blue-green is derfinitely noted as an iron-based precipitate, either from the combination of iron ions with tannic acids or from the iron compound of cyanide. If the latter, indeed I wouldn’t be happy about that showing up in the wine (especially as the wines are made by friends of mine, and I have fired off an e-mail to them to find out what their response is), if the former, it’s also not a good thing, though not dangerous, just simply would mean they’re doctoring the wine with additional tannin.

By: Ignacio

Ignacio — Mon, 15 Sep 2008 22:11:20 +0000

You can find an online form to submit the INV a complaint regarding consumer issues at http://www.inv.gov.ar/defensa_cons.php

Best regards,

Ignacio

By: Ignacio

Ignacio — Mon, 15 Sep 2008 22:02:34 +0000

Dan,

Thouugh not an expert by any means, I have never seen the crystals you have found in an Argentine wine.

If they were some kind of precipitate of potassium ferrocyanide (in the form of ferric ferrocianide, which I believe is its subproduct), I understand that -according to INV’s (Instituto Nacional de Vitivinicultura) regulations (specifically Resolution INV N° 106/92), it should not be present in any form in the wine. Perhaps you should consider bringing this to the attention of the INV officials since I understand they take these matters very seriously.

BTW, the admitted levels of chemicals in Argentina can be found here, at the INV’s website (http://www.inv.gov.ar/normativas.php?ind=2).

Best regards,

Ignacio

By: Allan

Allan — Mon, 15 Sep 2008 20:25:24 +0000

I’d guess the crystals are a precipitate of a copper sulfate solution. The solution, in varying strengths, is used to control fungal blight on grapes and other produce.
Yep, always wash your produce.