[Sca-cooks] Weird Kitchen Science: Fascinating color-shift phemonenon...

[Lonnie D. Harvel]

Careful!

 From a Colorado State extension website:

*Garlic.* If desired for flavor, use mature, fully-dried, white-skinned 
garlic, free of blemishes. Garlic contains a water-soluble pigment that 
may turn blue or purple. A blue-green color may develop in pickles made 
with stored red-skinned garlic. Immature garlic, garlic that is not 
fully dry, or red-skinned varieties may turn blue, purple or blue-green. 
/*Except in the case of a bright blue-green color */resulting from 
abnormally high concentrations of copper-sulfate, such color changes do 
not indicate the presence of harmful substances. (emphasis is mine)

Aoghann

Bill Fisher wrote:

>On Thu, 9 Dec 2004 22:33:44 -0500, Phil Troy / G. Tacitus Adamantius
><adamantius.magister at verizon.net> wrote:
>
>  
>
>>So, there I am caramelizing twelve pounds of onion/garlic/ginger
>>puree, and as I say, when I make a pint of this stuff I'm used to the
>>various sulphur compounds in the onion reacting with either the
>>ginger and/or the iron pan to produce a slight bluish-green color
>>which goes away as the product cooks (it turns grey, then brown, then
>>sorta reddish). I left the kitchen for a few minutes with my pans on
>>low heat, and came back to find an astonishingly bright aquamarine
>>blue-green stuff in the pans.
>>    
>>
>
>Thanks for the curry building blocks....I will use that this weekend.
>
>Hrm, blenderized onions plus water = sulfuric acid + iron pan....
>
>I don't have a clue......
>
>Maybe the onions came from an area with really high soil sulfur content?
>
>Do other onions turn colors in your pans?
>
>Do they do that in other pans?......do you have other pans?
>
>Were you wearing pants?
>
>Did they change color?
>
>
>  
>
>>I haven't seen any evidence to suggest this is either unnatural or
>>dangerous (if I'd been using an unlined copper or aluminum pan, I'd
>>be worried), but man, this was bright for a food product not
>>deliberately colored that way.
>>
>>Will advise if there's an explosion or anything...
>>
>>Adamantius
>>    
>>
>
>I'm curious how they turned out...
>
>Cadoc
>  
>