[Sca-cooks] Baker's borax from the other side.

[Terry Decker]

What you are talking about is a Maillard reaction, where the dough is glazed 
by dropping it briefly in a high pH (basic) solution.  It produces the shiny 
dark brown color on pretzels and pretzel bread.  It's a a common glaze on a 
number of German breads.  The common chemicals used produce the reaction, in 
order of efficiency, are lye (potassium carbonate, sodium hydroxide, 
potassium hydroxide), washing soda (sodium carbonate) and baking soda 
(sodium bicarbonate).  Potassium hydroxide has a pH of about 14, sodium 
hydroxide is around 13, baking soda comes in at 8.3, Armenian borax (borax 
pentahydrate, a form of borax) clocks in around 9.5.

IIRC, all of these compound are produced by shallow water deposition and 
evaporation (alkali pools), so multiple compounds are probably quite common. 
Unfortunately, the process of leavening is different from the process of 
glazing.

I've only experimjented with the technique a couple of times, so my empiric 
knowledge is limited.

Bear


> One of my al-Warraq puzzles is baker's borax. It's chief use seems to have 
> been to make bread loaves shiny. So instead of asking "does baking soda 
> make bread shiny," baking soda being one possible guess for baker's borax, 
> we could look at the question from the other side:
>
> What chemical that could have been available to al-Warraq would make bread 
> shiny? Is there any such chemical that would also work as a chemical 
> leavening? Alternatively, are there two chemicals, one of which makes 
> bread shiny and one of which works as a leavening, that might have been 
> found together in nature?
>
> I should add that my first experiment with painting a solution of baking 
> soda on bread was a failure--the half of the loaf I put it on came out 
> browner, not shinier. But I will try again with a lighter touch.
>
> Also that, on current evidence, possible candidates for samidh flour 
> include fine semolina, 00 flour, and ordinary white flour, with the fine 
> semolina perhaps a little ahead of the others.
>
> -- 
> David Friedman