Anyway, I tried it out, and had mixed results. The smell and flavor were vaguely reminiscent of dry-aged beef, but it didn’t have those same cheesy/funky/earthy background notes. As far as the texture goes, there was no difference from a regular steak, and it may have even given it a somewhat firmer texture.
That may have come from letting it go almost three days, instead of two, but hey, I was within the range. Besides, I’m not even sure anything happened. The idea here is that the fungus on the koji rice, which breaks down the proteins in beans, to make things like miso, would work the same magic on a steak.
While it did look like the koji had “bloomed” a bit, and there was more “white stuff” at the end of the process, there was no obvious signs that the meat had been “broken down.” The appearance was darker, and it kind of had that waxy look of dry aged meat, but that could’ve simply come from sitting uncovered in the fridge.
I found it a bit suspicious that there were no other posts regarding this online, but maybe it’s just too new. Time will tell. I'm looking at you, food blogger. In the meantime, any and all feedback is welcomed, especially if you are familiar with using koji rice. I’m not sure if you should give this a try, but, as always, enjoy!
koji rice (I used this one)