At this years Foodhackingbase I was attending a nice workshop on making tempeh. After the foodhacking event was over, Algoldor handed me some nice tempeh.
I never tried tempeh before that. I read on the internet that some people use it to make vegetarian bacon -- I'm not a vegetarian however. I marinated it like meat, and it's delicious.
Tempeh is originally a soy bean product. This batch however, was made with chickpeas. The beans were soaked overnight in water, peeled, and then cooked. Meticulously dried, they are mixed with flour (e.g. wheat flour) and the tempeh (i.e. rhizopus oligosporus) culture. Then it's time for the fermentation to do it's thing.
I used a contraption, made from a camping cooler, a temperature controller and a reptile heat mat, to heat the entire batch of tempeh to 34 degrees celsius for 12 hours. After theses 12 hours I set the temperature to 30 degrees. However the fungus started to produce its own heat and kept the temperature at approximately 32 degrees for the next 36 hours. After two and a half days I had half a kilogram of nicely fermented tempeh.
I enjoyed the tempeh very much, it tastes somewhat like beans, mild yet very umami. Several people report that their tempeh smells like ammonia, mine did definately not. While some black spores on the surface may be ok, my tempeh did not exhibit any of these signs, even after I left it for another day in the fermentor.
For the next batch I hope to complete a custom temperature controller that will be more capable than the current one I have.