Wine Experts/Chemists Please....
Wine Experts/Chemists Please....
Author
Discussion

theexcession

Original Poster:

11,669 posts

279 months

Wednesday 29th June 2005
quotequote all
[b]Potassium Tartrates[/b]

How do I test to see if the shards of glass like substance at the bottom of the bottle of Gewurztraminer are actually Postassium Tartrate (the wine distributers opinion) and not glass (our opinion).

We tried dissolving them into cold tap water but the crystals remain.

cheers
Ex

diddyman

3,646 posts

270 months

Wednesday 29th June 2005
quotequote all
I did a Brucie for you and trawled the internet:

"When placed in a Bunsen burner's flame, it turns purple."

How are the dawgs, BTW, Ex?

>> Edited by diddyman on Wednesday 29th June 09:54

>> Edited by diddyman on Wednesday 29th June 09:57

Andrew Noakes

914 posts

269 months

Wednesday 29th June 2005
quotequote all
My wine-making partner says look under the cork - if there are tartrates in the wine, crystals often form here. Bits of glass would just sink to the bottom.

I'm told that bits of glass would be very unlikely, but tartrate crystals are very likely - particularly in a good German wine.

Don

28,378 posts

313 months

Wednesday 29th June 2005
quotequote all
It is entirely possible that a Gevertztraminer could throw a desposit over a few years. It is very, very common for red wine/port etc to do so. A by product of modern organic techniques where less/no filtering of the product is done.

It is also, unfortunately, possible but vanishingly unlikely that in the bottling process a defect led to your bottle being defective.

But BY FAR the most likely reason is that the unfiltered wine has thrown a deposit.

Did you *like* the wine? If so consider investing in a proper decanting set in which you will find a "posh tea strainer" for getting rid of such things.

I really hope it wasn't glass. Clearly this would NOT be good for you!

Hope the above helps. Let us know what you find out.

theexcession

Original Poster:

11,669 posts

279 months

Wednesday 29th June 2005
quotequote all
Thanks all,

The wine was a 2002, and tbh was bloody luvly.

Looking under the cork is a bit of a problem as it's a New Zealand wine hence a screw cap

But this stuff has sunk to the bottom. We've got two of these bottles, one we drank the other is still sealed.

The one that we drank, we put some tap water into it and left it for a few days, the crystals are still there.

From the experience of spitting them back into my glass I can tell you that the have no flavour and are extremely hard (and a bit sharp).

I too am not certain that they are glass shards and if they are we need to prove it and claim our free crate.

So, I have one bottle unopened, one bottle opened drank and sitting with about 15ml of tap water in it. Both have crystals in the bottom.

What to do?

best
Ex



>> Edited by theexcession on Wednesday 29th June 10:14

Don

28,378 posts

313 months

Wednesday 29th June 2005
quotequote all
Chemistry master at the local school?

Second opinion from a different wine merchant?

theexcession

Original Poster:

11,669 posts

279 months

Wednesday 29th June 2005
quotequote all
diddyman said:

"When placed in a Bunsen burner's flame, it turns purple."

How are the dawgs, BTW, Ex?


Haven't got a bunsen burner any more

The dawgs are fine, thanks for asking, we took them back to kennels last week. Went to see them again last night and the boy hound knew us straight away, came up to me and buried his head into my coat and wouldn't leave me. He just stood there wimpering to me. When we went to leave he was the one who stood with his legs high on the fence barking and howling... got the feeling he wanted to come home with us. Brought a tear or two to my eye if the truth be known.

The bitch pup was just that and didn't seem the slightest bit interested in us.

best
Ex

mechsympathy

58,637 posts

284 months

Wednesday 29th June 2005
quotequote all
theexcession said:

diddyman said:

"When placed in a Bunsen burner's flame, it turns purple."

How are the dawgs, BTW, Ex?



Haven't got a bunsen burner any more


Have you got a blow torch?? You can get gas soldering irons with a flame nozzle for less than a tenner. (I assume, as they produce a blue cone in the flame, they're hot enough.)

love machine

7,609 posts

264 months

Wednesday 29th June 2005
quotequote all
I reckon it's better that the wine has dropped it's load rather than be excessively acid.

Harmless stuff.

D_Mike

5,301 posts

269 months

Wednesday 29th June 2005
quotequote all
are they single crystals? (are the crystals regularl shaped with sharp edges, are they shiny and are they transparent?) stick em on a diffy... www.bruker-axs.de/index.html?page=/products/gd/d8_advance.php

or er.. melting point analysis, or NMR if you want to pay someone to do it for you (assuming you dont have an NMR machine + knowledge on how to use it handy).

apparently 1g goes into 700ul of water so it should dissolve in water... try heating them and seeing what happens, do they melt? What if you put it in some vinegar and see if that dissolves it?

edit: not sure about the flame test.

>> Edited by D_Mike on Wednesday 29th June 10:21

theexcession

Original Poster:

11,669 posts

279 months

Wednesday 29th June 2005
quotequote all
Can't do a flame test, no gass out here in the sticks of Ireland, but...

Melting Point Analysis - should've thought of that.

I'm off to melt some in a tea spoon on the stove.

brb
Ex

D_Mike

5,301 posts

269 months

Wednesday 29th June 2005
quotequote all
theexcession said:
Can't do a flame test, no gass out here in the sticks of Ireland, but...

Melting Point Analysis - should've thought of that.

I'm off to melt some in a tea spoon on the stove.

brb
Ex


I think it decomposes rather than melts... not sure what temp though.

theexcession

Original Poster:

11,669 posts

279 months

Wednesday 29th June 2005
quotequote all
boooo

Certainly looks like it isn't glass. A quick blast from the halogen hob turned the crystals into a white colour. They then became soft and powdery.

Ho hum, there goes my where there's blame there's a claim opportunity.

best
Ex

Edited to say: 2nd bottle has just gone back into the fridge, later I shall mostly be drinking a 2002 Gewurztraminer

>> Edited by theexcession on Wednesday 29th June 10:36

Zod

35,295 posts

287 months

Wednesday 29th June 2005
quotequote all
They are almost certainly tartrate crystals. Very common in German and Alsace wines.

Don

28,378 posts

313 months

Wednesday 29th June 2005
quotequote all
Get yourself a decanting set. Well worth it.

Easy peasy:

1) Prepare large jug so it is spotlessly clean.
2) Pour wine through filter into aeration cup - draining into the jug
3) If red/cheap/thirsty serve in the jug.
4) Wash bottle out thoroughly
5) Optionally pour wine from jug through aeration cup a second time 0 draining into the bottle.

You lose no more than a few drops and can pour the wine with impunity, even the last glass.

They're only a few quid, I believe...