[Sca-cooks] Another leavening agent was Baker of Bagels in the 11th C

[Terry Decker]

>
> http://slurpandburp.blogspot.com/2006/01/imbb-22-lamian-chinese-stretched.html
>
> This is a fairly lengthy blog diary on northern Chinese pulled  noodles, 
> containing something of an argument between readers/posters  on whether 
> they do, or should, contain a small amount of borax, and why.
>
> The consensus among the people that think it belongs in those noodles 
> seems to be that in noodles, it's about gluten extensibility, which, 
> given the high gluten flour traditionally used for bagels, could be  said 
> to make some sense.
>
> Adamantius

I knew I had seen information on water hardness and gluten formation.  There 
is an entire section in Paula Figoni's How Baking Works.

According to Figoni, minerals harden gluten, making the strands so elastic 
that they don't stretch properly to trap the CO2 in fermentation.  The 
higher the gluten content, the worse the problem.  When you reduce the water 
hardness, you reduce the spring back in the gluten strands and allow them to 
properly extend.

The most common minerals in hard water are calcium and magnesium.  Borax 
will react with calcium and magnesium in solution neutralizing the effect on 
the gluten (I suspect the minerals will precipitate out and become part of 
the solid matrix, but I haven't researched that).  Interestingly, desert 
regions often have hard water.  Northern China, North Africa, the Middle 
East?

There is also a pH factor involved, calcium carbonate being on the acidic 
end of the scale and borax being basic, but that's a little different from 
the issue of hardness.

Next time I'm in NM, I'll try adding a little baking soda to the mix to see 
if I can get a better rise.

Bear