[Sca-cooks] Borax as leavening?

[Terry Decker]

I can see adding borax as a tenderizing agent, but I question the leavening. 
The chemical leavens I'm most familiar have a CO3 molecule that converts to 
CO2 and water.  Borax is NA4B2O7.  During disassociation (if I got the term 
right), I would expect the O7 to recombine as H2O rather than O2.  The 
fastest way I know to test would be prepare a recipe and see what happens.

We discussed a similar issue in Soup for the Quan.  I believe the discussion 
is in the Florilegium and includes Paul Buell's response to our comments.

I've never heard of using borax as a leaven, so it would be interesting to 
see if this is the author's interpetation or if there is source material 
that supports the use.

Bear

> It'll be a while until i finish reading "Annals of the Caliphs'
> Kitchens" - i'm working my way through the introductory matter, and
> periodically plunging into the cookbook text and the glossaries.
>
> While taking a plunge, i read that borax was used as a leavening in
> Near and Middle Eastern breads. The recipes often don't specify what
> sort of leavening to use. So i'm curious, never having cooked with
> borax... how does it work? Does it function somewhat like baking soda?
> -- 
> Urtatim (that's err-tah-TEEM)