Is this koji maturing or already sporing?

Hello, I have attached 2 pictures of the koji I made in my egg incubator; I am very hopeful that the koji is still in the maturing stage, and not quite in the sporing stage. It is not white, but I have read on the forum that it may still be okay to use if it is not green. I will keep it in the fridge until I know whether it can still be used for sake.

My sake homebrew kit mentions that it should look white or slightly tan; would this qualify?

Also, the conditions were generally 96 degrees F, and a moist environment. The rice was very moist at the end of the process.

Without macro images, I can’t really say whether you have bad rice or just yellow koji on your hands there. Usually that kind of shiny yellow is bare steamed rice, with no koji covering at all. For contrast, this is what my finished koji looks like:


Click to enbiggen.

Ok, I started a batch of moto with that koji, and I don’t know if it’s good or not. It sure smells like it’s fermenting, but I haven’t added any yeast at all. Also, I’m not quite sure what you mean by liquified in your manual. It started off by soaking up all the water, now it’s more liquid but the shapes of the rice are still very distinct. Should I keep going?

It smells like it’s fermenting? What do you mean? I mean, if you have an airlock on, then you should know if it is fermenting or not.
Also if it is fermenting and you haven’t added any yeast yet, then this is a bad sign. You will probably have a very sour moto with a very high concentration of lactic acid bacteria. This is one of the drawbacks of using a yamahai moto. You should try a sokujo moto as explained: www.sakebrew.com/sake-brewing-recipe