[Sca-cooks] blue food coloring

[Pixel, Goddess and Queen]

>
> On Sunday, February 2, 2003, at 06:47 PM, Nancy Kiel wrote:
>
> > Can anyone suggest a period blue food coloring?  I looked into
> > turnsole, but
> > it comes from heliotrope which is poisonous.  Thanks!
>
> Blue seems to have been a tough color - In The Colorful Cook [Renfrow &
> Fleming, CA#109] I find lots of ways to get reds, yellows, and greens,
> but very few blues.
>
> Cindy Renfrow (are you reading this, Cindy?) may be able to point you
> towards others (or those that I missed), but here's what I found:
>
> 	elder bark
> 	the flowers of bluebottles (Campanula or Scilla species)
> 	borage flowers (Borago officinalis)
> 	indigo (is indigo food safe? the indigo dye vat my wife uses certainly
> doesn't smell like anything I'd want near food)
> 	woad (is woad food safe?)
>
> There are others listed (such as copper carbonate and cobalt-based
> ground glass), but they were also noted as being generally bad for you
> (i.e. toxic), so they're not any more suitable than turnsole.
>
> - Doc
>

Blue is not a common color in nature, and it appears to be the most
fragile--blue flowers fade the fastest, for instance. Indigo (and woad,
it's the same pigment) is inert when blue. Synthetic indigo is merely
indigotin in powder form.

The fermented urine (or the lye, if you're being modern) has nothing to do
with the indigotin being blue, it's how you reduce it so that it will
adhere to the fiber you are dyeing. An indigo vat is not blue, it is light
yellow-green. It has to oxidize before it will turn blue.

That said, I have never found a satisfactory answer to my question as to
whether inert indigo is toxic or not.

ISTR the mention of alkanet being used as a blue colorant, but I couldn't
say where. Elderberry juice with alum is "blue", but it is very touchy and
prone to turn a greenish-gray. Without alum it is pink/red. Elderberry
syrup like my grandfather made, dyed the pancakes blue-purple.

Margaret