My Natto seems to fail for no apparent reason. I created one very good batch, nice smelling, good stinginess and slimey threads, but I don't seem to be able to repeat this. I have three failed batches now, tried different starters, different soy beans, to no avail.
I soak the beans, pressurecook until soft. Put in clean glass Pyrex pot, mix in the starter, stir well, let cool down to 40 C, cover with cheesecloth and Pyrex lid, allow some air, put on bottom of Brod&Taylor proofer in an steel scale with a bit of water and ferment in slow cook mode at 40 Celsius.
After 12-14 hours there is a small white layer over the beans and they smell lovely, in fact, the whole house does. However, there are no threads. The beans are dry, not stingy so it looks like for one reason or another the Nattokinase did not start. I stir, allow the process to contine but the beans only get dryer so after 24 hours I put them in the fridge. After several days no improvement, still no stinginess or Natto strings.
As far as I understand for Natto to be effective for health it should have these slimey strings after stirring. My first batch did.
I have no clue what's wrong, hate to throw away food, so your advice is most welcome. Thank you very much!