A fermenter was made from parts supplied commercially. The heater is a warmer off the internet Lee Valley about 25 dollars delivered. The container 6 US gallons is from a store that makes wine for about 5 dollars. The rack is from a paper supply store Staples for about 4 dollars. The temperature is from 30C to 35C centered on 31C. It can be modified slightly by opening and closing the lid. Tempeh is made in 500 ml batches three types soy, chickpea and red lentil.
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