Shio Koji Burger, Umami Magic

I recently met with my friends, Alex and Aki, of Ideas in Food to share knowledge on the subject of koji. We had a conversation a couple years ago on the potential for an idea exchange, which lead us down this tasty rabbit hole together.

Shio Koji Cheese Burger Pizza

This all started a while back when I brought over some homemade koji and miso for a tasting. They appreciated the flavors coaxed from the combinations I shared. However, Alex's biggest hang up with everything that's made with koji is the overpowering characteristic flavor. To my understanding, a key concept of Ideas in Food is to make food better than itself. So what does that mean? For example, a steak should taste like the most delicious beefy steak you've ever had, not a miso steak. Not an easy feat.


Jasmine Rice Shio Koji
We were sitting in the kitchen milling over potential experiments then Alex broke out his brown rice & barley shio koji. I also happened to have a Jasmine rice version on hand. It only made sense to see if we could leverage the umami magic while pushing the "soy sauce" flavor into the background.

Shio koji is a Japanese meat marinade powered by enzymes to break down proteins into delicious amino acids, umami. It consists of a slurry of rice/grain koji, water and salt that has fermented for a week or two. The cool thing about applying shio koji to meat is that it produces flavor depth that by default matches the base product.


Just Formed Burgers: Brine, Barley, Jasmine and Brown Rice Shio Koji
We gave some thought to what would dial back the koji flavor and still produce enough depth. The straightforward answer was to use as little as possible. Considering that, optimizing the effectiveness of the marinade was important. Surface area contact is a driving factor, so it only made sense to use ground meat. Hence, the umami burger experiment...


Burgers Post Overnight Marinate
We started by tasting the three marinades (barley, brown & Jasmine rice), which all had unique flavors ranging from the former as the most complex to the latter as sugar forward. We used a 10:1 ground chuck to shio koji ratio and mixed it together. For our control, we used a brine to match the 1% salt content of the other burgers.


Brine Burger in the Back, Jasmine Shio Koji in the Front
Upon grilling, there was an obvious indication of which burgers had the shio koji treatment. Clear charred markings as a result of the caramelization of sugars from the grains. 


Shio Koji Burgers Ready for Tasting
Finally, after all that effort, we tasted the results. It worked pretty well for our first try. The umami level was pushing the limits in all of the shio koji burgers. Also, we could taste a transformation of the base koji grain flavors married with the meat. The Jasmine sweetness was the least favorite. To my palate, the brown rice had nutty notes and barley tasted mushroomy.

At the end of the day, this concept has shown great promise and it won't take many more iterations to make the burger of your dreams.

As always, please share your discoveries to keep the ideas bouncing.