2 cups soybeans
3 quarts water
2 tbsp apple cider vinegar (optional)
one packet of tempeh starter culture
In a large bowl or pot, soak 2 cups of soy beans in 3 quarts of water with the vinegar (if using) overnight or for 10-12 hours. Remove the hulls by massaging the beans with your hands until the beans are all split and the hulls float to the top. Use a colander to drain out the water and continue rinsing/massaging until all hulls are removed.
Cover de-hulled beans in a new pot of water, heat to a boil and simmer for 1 hour. Discard the cooking liquid. Dry the beans by patting them down with a towel and transfer to a dry bowl. Let them cool to a lukewarm temperature (about 95 degrees F).
Add tempeh starter culture. Mix very well.
Spread the beans into a layer 1-1.5” thick in a ventilated container (a plastic bag with pin holes space 1” apart works well). Culture at 85-92 degrees following our Fermentation Incubation Hacks for 24-48 hours checking the temperature intermittently. After 12-24 hours the fermentation should create and maintain its own heat, so remove heat source accordingly. After 24 hours white spores will begin to cover the surface of the beans. After about 36-48 hours, the beans will become a firm mass held together by the white spores. Note: this could take up to 4 days.
Transfer to a sealed container for up to 3-5 days in the fridge or 2 months in the freezer.