[Avodah] Yeast isn't chameitz

[Michael Makovi]

Something I just talked with someone about this very Shabbat:

Given that matzah meal cannot become hametz, cannot one easily bake
bread on Shabbat using matzah flour?

However, if the process of cooking the matzah has degraded the gluten
in such a way that it cannot rise properly anymore, couldn't one add
baking powder, and chemically cause it to rise? (Yeast is biological
leavening; whereas any powder that produces carbon dioxide is chemical
leavening. The major difference is that yeast's metabolizing the
gluten also produces various chemicals that affect the flavor of the
bread; chemical leavening will not do this. -
http://en.wikipedia.org/wiki/Leavening)

So does anyone take advantage of this to bake wheat/barley-based
breads on Pesah? I'm rather amazed that no one I know does this. (Of
course, if someone did this, it would only make the prohibition of
kitniot even more difficult to understand.)

Now, because the matzah may not rise properly with only yeast, and one
may have to resort to chemical leavening, traditional breads (which
require the "yeasty" flavor) might not be advisable, but quick breads
(Pesadic wheat-based scones, anyone?) would be perfectly feasible on
Pesah, if baked from matzah flour.
http://en.wikipedia.org/wiki/Quick_bread

Oh, and we see that halakha is not concerned with the technical
process of biological leavening via yeast, from the fact that fruit
juice does not produce hametz, even if the yeast does metabolize the
gluten and cause the bread to rise. Even though the technical process
of leavening HAS occurred, it is NOT hametz. But were halakha
concerned with yeast per se, surely this fruit-juice-leavened bread
would be hametz, but in fact, it is not!

Michael Makovi

-- 
Michael Makovi
מיכאל מאקאווי
mikewinddale at gmail.com
http://michaelmakovi.blogspot.com