I've tried several times and several variations, but I cannot not get okara tempeh to work. I've worked with different dryness levels, different starters, different incubation temperatures. Either nothing grows at all, or the growth is very spotty. I have great success with many other kinds of tempeh. I make several batches of regular soybean tempeh every week.
I have a lot of okara on hand from making soymilk, and I'd like to put it to use in some way. I'll put some in baked goods, but I have far too much okara to use up this way. The other use I've found for it is to cook it up with eggs for my dogs--they love it.
Information on the exact details of making okara tempeh is sparse. I've read The Book of Tempeh and some other sources on the internet, but I've been unable to figure out what is causing my lack of success.
Working with the okara pulp leftover from 4 cups of soybeans that has been frozen (I've also worked with fresh-not-frozen with the same results), my basic method is to first pressure steam the okara for a half hour. Then I add 1/4 cup of vinegar and dry it out in a pan on the stove. Finally, I cool it down, add the starter (2 tsp), transfer it into perforated bags (keeping it from getting packed down), and incubate at 86F. The okara is visibly dry, but when I squeeze a handful, a little liquid comes out, but just enough to get my hand damp, not enough to drip.