On the right is a koji I made a few days ago – rice koji starter on eco rice. On the left is the same rice substrate but using starter for barley koji instead. 

As I figured, it sporulated earlier, more profusely and with a much darker green color. It will make a darker miso with perhaps a stronger flavor, but I’ll have to make a couple parallel batches of miso to see and taste the resulting misos after another 2 years.