It's been my experience that kombu generally doesn't break down.
Also, it takes a long time for the kombu to enhance the flavor of the
beans.
Kombu is added to beans because it is a source of glutamate, a salt or
ester of glutamic acid. It is my understanding that it is the same
ingredient that is used in MSG, but NOT the same as MSG.
My sister, for example, gets a migraine just by looking at MSG on the
shelf in a market (only a slight exaggeration), but has never had ill
effects from eating beans or even the kombu itself.
Ciao...Bev
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