Just last night I started my first batch of homemade tempeh, a food
I've enjoyed for years but have never attempted to make before. It's
progressing beautifully in my makeshift incubator, and I expect it to
be finished by late tonight.
My question is this: Is the tempeh for sale in stores (i.e. White
Wave, etc.) already cooked? I ask because the literature on
tempeh-making I've read says that fresh (homemade) tempeh will keep in
the refrigerator for 3 - 4 days, yet the White Wave brand tempeh I
purchase has a sell-by date of one month or more from the date I
purchase it. So has the store-bought tempeh been cooked or otherwise
treated to preserve it somehow?
This raises another question: Will homemade tempeh keep for much
longer if it's steamed just after it's made, then stored in the
refrigerator? I know it can also be frozen, of course.

Neal