Archives for posts with tag: Mycelium

It’s the second day (36 hours). The tane koji (starter) spores have long since germinated and the mycelium has grown so much that it has started to bind the rice corns into a cake.

The smell is right – delightfully sweet and fruity. The temperature is right after a slight adjustment, and the moisture, tho a little on the wet side, is OK. Now I’ll break up the clumps while adding air and put it into the heat chamber for another 12 hours.

At the same time the next batch of rice is washed and soaking for tonights steaming.

Step 7

The morning of the fourth day

The mold has not blossomed yet but is just starting to. The fuzz of the mycelia is beautiful, and the odor and flavor are wonderful. The enzyme level should be at its very best now, so I will harvest it anyway.

On flowering it will turn a nice yellow tan color. Many koji makers let it go that far. Perhaps this adds to the flavor and color of the miso. I seldom let it go so far and haven’t noticed any difference in the miso.

I scrape the mass onto cloth lined drying baskets and spread it out.


These baskets go on a rack in the furnace room to dry for 2 or 3 days.

The next and last step will occur in about 2 days when I check for dryness, package and save for later miso making.

And now is the time to put rice to soak for the next batch. I will make up to ten batches of rice and barley koji during the winter season.

Step 6

Now is the evening of the third day

The mold has been growing in the heat cabinet for 2 days at about 27 degrees centigrade. The rice now has a furry covering of aspergillus mold which cakes the whole mass together. The dampness, odor and taste are perfect.

Usually I harvest it at this time, but this time I think I will let it grow 12 more hours to get a little color as the mold flowers. So I aerate again and put it back into the cabinet.

Next step tomorrow morning – harvest