Started a batch of natto this evening. 600g of dry soybeans soaked about 8 hours, then pressure cooked for 20 minutes. Mixed in some spores, put a thin layer of the beans in these glass containers, then covered with a damp cloth and lids. I’ll keep these in my makeshift incubator (a cooler with a reptile cage heating mat) overnight at 40C, then put them in the fridge in the morning, and enjoy them the day after.
That looks really interesting! I make lots of tempeh at home, but I’ve never heard about “natto” before. From reading the wiki I can see that the microorganism is a specific variant of Bacillus subtilis bacteria. Where did you get your spores from?
I’m in Taiwan, and we have reasonable local access to various spores from Japan (especially for Koji and natto) through a few online retailers.