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Author Topic: Why Has The Foil Changed Colour ? (US translation "colour"= "color")..sheesh !!  (Read 9116 times)

Offline neilep

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Dearest Foiled Attempters and foilologists ,

See this silver foil ?



Nice eh ?....notice how the central roundish bit is a different colour ?

This happened after just a few minutes of use wwrapped over over a bowl of soup I had made !

Why did it change colour ?..what happened ?


I'm upset !..I wrote to the Silver Foil fairy but she was clinging to the film of a wrapped sandwich wrestling with the plastic wrap fairy for wrapping supremacy !...so, no answer there then !

Can ewe help ?

I want to know because I want to know ...and ewe want to know too !

hugs and shmishes



Neil
Wrapped In Foil Ready For Roasting


mwah mwah mwah mwah !


xxxxxxxxxxxxxxxxxxxxxxxxx





 

lyner

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Never happens to me. It must be your cooking!
 

Offline RD

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The oxide layer on aluminum can be dyed...

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The most common anodizing processes, for example sulfuric acid on aluminium, produce a porous surface which can accept dyes easily.
http://en.wikipedia.org/wiki/Anodizing

Your soup may be acidic, (hopefully not sulphuric  [xx(] ).
« Last Edit: 24/08/2008 18:28:39 by RD »
 

Offline neilep

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Never happens to me. It must be your cooking!

A bowl awaits ewe !.....it's good for releasing barnacles of the hull of boats too !!
 

Offline neilep

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The oxide layer on aluminum can be dyed...

Quote
The most common anodizing processes, for example sulfuric acid on aluminium, produce a porous surface which can accept dyes easily.
http://en.wikipedia.org/wiki/Anodizing

Your soup may be acidic, (hopefully not sulphuric  [xx(] ).

Thank Ewe RD

It was a vegetable soup....lots of onions if that helps !...and root vegetables !

Could temperature have anything to do with it I wonder...The soup was still warm..not hot !..

Thanks for the links by the way !
 

Offline RD

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If the soup was the same colour as the aluminium foil then its oxide layer has simply absorbed the vegetable dyes.
[If the soup was the same colour as the aluminium foil I don't want any  :)]
Maybe vinegar (acid) in your veggie soup could assist the dyeing of the aluminium oxide layer ?
« Last Edit: 24/08/2008 19:14:11 by RD »
 

Offline neilep

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If the soup was the same colour as the aluminium foil then its oxide layer has simply absorbed the vegetable dyes.
[If the soup was the same colour as the aluminium foil I don't want any  :)]
Maybe vinegar (acid) in your veggie soup could assist the dyeing of the aluminium oxide layer ?


Hmmmm...well, the colour is close....ie: the colour of the changed foil is similar in colour to the soup.........I think ewe've nailed it !

Ta RD

A cup of soup awaits ewe !
 

Offline RD

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A cup of soup awaits ewe !

Err, no thanks. If it was carrot and orange that would be a different matter.
 

Offline Karen W.

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I want some ... I'm not sceered of your soup.. Sounds yummy!

when I cook with parsley sage rosemary and time with my turkey noodle soup.. a tad of olive oil and some other good vegetables ie celery carrots etc, My foil will also turn that color.. It looks familiar.. I always thought it was the ingredients and an acid base!
 

Offline rosalind dna

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Neil it might have been the condensation rising from your soup along with the acids in the onions and other ingredients that have caused the change in the colour to the foil.

That happens to me if I bake something like fish or do a roast (rarely).
 

Offline neilep

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A cup of soup awaits ewe !

Err, no thanks. If it was carrot and orange that would be a different matter.

I do make a really luffley carrot soup....not with orange, though I know it's a popular combo !

Making barley soup tonight !....*le yum*
 

Offline neilep

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I want some ... I'm not sceered of your soup.. Sounds yummy!

when I cook with parsley sage rosemary and time with my turkey noodle soup.. a tad of olive oil and some other good vegetables ie celery carrots etc, My foil will also turn that color.. It looks familiar.. I always thought it was the ingredients and an acid base!

Okilydokily.....if ewe can find a straw long enuff then my soup's all ready for ya.:)

Glad to know it's not just me who has the colour changing foil thing !!
 

Offline neilep

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Neil it might have been the condensation rising from your soup along with the acids in the onions and other ingredients that have caused the change in the colour to the foil.

That happens to me if I bake something like fish or do a roast (rarely).

Hi Rosalind,

Yep, methinks ewe are right about the condensation thing, and about the opinion's and acidity stuff too !

Good, as long as it's not doing any harm then I can come down from red foil alert to blue foil alert :)
 

Offline Karen W.

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I want some ... I'm not sceered of your soup.. Sounds yummy!

when I cook with parsley sage rosemary and time with my turkey noodle soup.. a tad of olive oil and some other good vegetables ie celery carrots etc, My foil will also turn that color.. It looks familiar.. I always thought it was the ingredients and an acid base!

Okilydokily.....if ewe can find a straw long enuff then my soup's all ready for ya.:)

Glad to know it's not just me who has the colour changing foil thing !!

LOL.. Thanks.. You know thinking about it My Chicken noodle soup does that and both of those contain Bouillon!
 

Offline rosalind dna

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Neil it might have been the condensation rising from your soup along with the acids in the onions and other ingredients that have caused the change in the colour to the foil.

That happens to me if I bake something like fish or do a roast (rarely).

Hi Rosalind,

Yep, methinks ewe are right about the condensation thing, and about the opinion's and acidity stuff too !

Good, as long as it's not doing any harm then I can come down from red foil alert to blue foil alert :)

Neil it's the very same acids in the onions when they are realised make people "cry" me for one.
Not dangerous sort or I wouldn't eat onions.
So it's just the concensation and any acids from the food in your soups or foods. I reckon
 

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