How to get a 45-day-aged steak in only 48 hours: Cooking with koji (and science!)
How to get a 45-day-aged steak in only 48
hours — Cooking with koji (and science!)
Koji is a fungus from Japan that ferments
Its spores grow on cooked rice.
When applied to steak, its powerful enzymes
break down proteins and slowly tenderize meat.
Number 1. Here’s how you age a steak with koji rice.
Buy koji rice at a Japanese market or online.
Then crush the rice in a blender.
Number 2. Dry rub your meat.
With koji, any cut of steak will do.
Take the blended powder and rub it on all
sides of the steak.
Koji works well turning an average cut of
meat into a way above average eating experience.
Number 3. Let science do the work for you.
Put the steak on a wire rack so the koji can
Pop the steak in the fridge for a full 48
After 12 hours it will look like a snowy slab
as the enzymes break down the flesh.
After two days in the fridge, the steak is
Number 4. Scrape and rinse.
Use the back of a knife to scrape off the
What you’re now holding should look dark red
and dried, just like an aged steak.
Rinse the steak in cold water to get rid of
the remaining koji.
Number 5. Sear it!
In clarified butter, pan sear the steak for
about 4 minutes, until it forms a dark crust.
Season with salt and pepper.
Be careful because koji steak caramelizes
much faster than a non-treated steak.
Pop it in a preheated, 400-degree oven for
about 4 minutes for a medium rare steak.
Take it out, then let sit for 10 minutes…
Now all you have to do is slice and serve!