On Sun, 8 Oct 2000, S. Feldman wrote:

> What is it that is referred to as residue after eating the various food items
> said to leave an acidic or other residue?

I gather that these are amino acid molecular "side chains" that
are attached to the protein molecule.  The impression I get is
that, for reasons unclear to me, these residues are not utilized
with the rest of the protein -- they resist the action of the
protease enzyme -- and are therefore buffered and excreted.

There's some stuff on amino acid residues here:
http://cmgm.stanford.edu/biochem118/protein-intro.html

Todd Moody
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