On Sun, 11 Jul 2004 08:13:52 -0500, ScratchMonkey
> wrote:

>Frogleg > wrote

>> And before you ask, no, you can't just add baking soda *instead* of
>> yeast to a bread recipe. The entire process is different.
>
>Can you say more about that, or provide a link?

http://users.rcn.com/sue.interport/food/leavning.html
>
>I recall as a kid making "rockets" with soda bottles and corks, mixing
>baking soda and vinegar in the bottle to launch the cork. So I'm familiar
>with the amount of gas that's produced.

As your science experiment should have told you, it's the reaction of
baking soda with liquid acid that produces carbon dioxide. See:

http://users.rcn.com/sue.interport/food/bakgsoda.html

Yeast (and water and flour) also produces carbon dioxide as the yeast
reproduces. It does not require the presence of acid for the process.
It *does* require time. Yeast breads acquire their 'puff' through a
couple of periods of slow rising before baking, and a final
push/growth spurt in the oven.

Single-acting baking powder gives its all the minute it is activated
by liquid. It does not sustain the reaction over time. Double-acting
baking powder is activated initially by the same chemistry, and
somewhat further by a slower-acting acid in the oven.

If you add baking powder instead of yeast to a simple (water, flour,
salt) bread recipe, you will produce a flour, water, salt, and baking
powder cannonball. There will be no lift because there is no acid. If
you add baking powder and, say, lemon juice, you may produce a slab of
cement with some holes in it. Still, nothing resembling bread. Note
that yeast breads increase 3-4 times in volume over the original
mixture; quickbreads and biscuits, more like 1-1/2 times.