Adventures in Food Fermentation: Koji Brisket Sandwich

For the past two and a half years, I have joked with the owners of Escarpment Labs about buying an oven for staff use. Each time I mention it, I seem to be getting closer and closer to approval. I have finally persuaded them enough to let me schedule a monthly staff lunch, catered by yours truly. Fortunately, I was able to sway the powers that be by leveraging some of the cool research and trials I have done on alternative food microbes which started as a side project when the world shut down in March due to the COVID-19 pandemic. 

At a time when many people were learning how to make sourdough bread, I was able to set up a small “lab” in my kitchen with some borrowed and unused equipment from the lab. Complete with a small incubator, some koji and tempeh spores, and my own personal oven, I set out to learn as much as possible about these incredible microbes. I wanted to learn how to use them, to see how they function in different applications, discover the ideal ways to grow them, and most importantly develop delicious recipes.

So what is koji and tempeh? Well, I'm glad you asked. These are molds, used to transform grains from simple starches to complex flavours, bound together using the power of mycelium and filamentous fungi. Rhizopus oligosporus, otherwise known as tempeh, hails from Indonesia, where it is believed to have been domesticated several hundred years ago. It is traditionally grown on soy, and creates an environment that can inhibit some nasty Gram-positive bacterial pathogens. The final product is a white moldy cake chalk full of enzymes that break down the proteins and create a unique, often nutty meal. Koji on the other hand, is a domesticated Aspergillus mold. Some Aspergillus can be deadly, and this is why, in domesticating koji, albino molds were often used to help reassure the user that their growth was safe for consumption. Koji is an enzymatic powerhouse, and unlike tempeh which is typically consumed shortly after the ferment finishes, koji often gets used in a second stage of fermentation, which occurs in products like Shoyu or Miso. Over months or even years, the enzymes help break down proteins and starches to create amino acids and the beloved fifth flavour, Umami.

Since March, I have experimented and created two batches of Miso (salt + koji + grains or legumes) and countless batches of Shio Koji (salt + koji) and Koji Flour (koji-inoculated grain, dried and milled)  in an attempt to create the perfect product. I also made soy sauce, a koji beer and over 10 lbs of tempeh. For me, working with these microbes in cooking is deeply satisfying, and blends both the world of science and the world of food together to create something truly unique, and delicious. Utilizing microbes in the kitchen, and seeing enzyme production and flavour creation beyond the world of beer has been exhilarating.

I plan to break down the process and experience of all of these tasty fermented foods in several blog posts, but for now, I want to talk about our first staff meal. The first staff meal centred on a smoked brisket and veggie burgers. In true Escarpment fashion, you may be asking “WHERE'S THE FERMENTATION?” Well, let me introduce to you the full menu, item by item. 

ITEM 1: Cured Shio Koji Marinated Montreal Style Smoked Meat

I am no newbie to making a great brisket. However, I was looking into incorporating something I had learned from quarantine into the next batch I made. The usual brisket recipe that I use is inspired by Noah Bernamoff's “Mile End Deli” in New York City. It consists of a lot of garlic, pepper, and coriander as well a bit of prague powder number one (a curing salt). It is then cured for 2 weeks in the fridge. This is almost the antithesis of fermenting, as it uses nitrates and salt to inhibit microbial growth. 

As a twist, after 10 days of curing, I switched things up and rinsed the cure off and slathered the meat in shio koji to tenderize and incorporate more umami to the exterior of the meat. Koji is packed full of enzymes which can help to break down proteins and sugars. In meat, this can serve to enhance the Maillard reaction as well as unlocking deeper umami. I didn’t use koji in the cure after some consultation with some Koji experts who suggested that using Shio Koji in the cure could risk over-tenderizing the meat, breaking down protein prior to the long smoke. 


Finished brisket before slicing

Plate of finished shio koji marinated and smoked brisket


Shio Koji 

Shio Koji is koji mixed with water at a 1:1 ratio, and then salt is added as a total of this weight. I have found the sweet spot to be 5% salt by weight. Some choose to start using these immediately, while others will ferment this mixture for a week or so at room temperature to get some light funkiness, with the salt back in the flavour profile slightly. 

What can you use Shio Koji for? So far, I have only used it to marinate meat. Thinner cuts only need a few hours, while thicker cuts can benefit from a full day of marinating. Other uses for Shio Koji included adding eggs, in a salad dressing or sauce. Pretty much anywhere you would use salt, but using twice the amount of Shio Koji to salt. Beyond its saltiness, Shio Koji still has enzymatic power from the koji that tenderizes and helps convert proteins into amino acids. It's a quick version of Miso, using simple ingredients and significantly less time. 


Shio koji being brushed onto the brisket during the cure


ITEM 2: Koji Flour Soft Buns

What sandwich is complete without buns? Koji flour has been another very exciting ingredient to emerge from our experiments with Koji. It is inspired by the 'Noma Guide to Fermentation', although we are using jasmine rice instead of barley as the substrate. Koji flour is dehydrated and milled koji. It contains ample amounts of simple sugars broken down by the koji, as well as some enzymatic power that helps with browning and promotes the continued breakdown of starches and proteins when incorporated into a dough. It can also be used in a batter or on proteins directly. We have found a little goes a long way with koji flour, and are hovering around a 5-7% addition to doughs.

The dough retains a delicate sweetness, as well as a bit of an umami goodness. This should pair PERFECTLY with both the brisket and the Veggie burgers for our beloved vegetarians. For the buns, we modified a recipe for Japanese Milk Bread, which uses a flour + milk roux mixed into the dough to enhance tenderness. Here, we replaced the wheat flour and milk in the roux with koji flour and oat milk. The result was tasty: sweet in a Wonder Bread kind of way, pairing well with the brisket and tempeh. 

Koji brisket sandwich


ITEM 3: Tempeh Burgers

Fear not, Vegetarians! Jonah to the rescue! Another exciting microbe that we have been exploring is Rhizopus oligosporus, commonly used to produce Tempeh. Tempeh burgers are a nutty, funky, earthy alternative protein that also brings a bit of meaty texture to a vegetarian BBQ experience. Tempeh mold binds grains and pulses as its mycelium penetrates the cooked substrate. Tempeh fermentation increases the protein content of its substrate, as well as adding additional fibre and vitamins. We made traditional soy tempeh for these burgers. 

In addition to the above items, we had an array of fermented accoutrements on offer: a lacto-fermented (Lacto Blend 2.0) garlic scape spread, kimchi, and fermented hot sauces from several staff. 

Why are we doing this? 

We have chosen to feature these microbial ferments as a staff meal, as this captures the unique purpose of these microbes, to create flavours and meals that can be shared with our community. As we continue to explore more applications of these amazing microbes by exploring new food recipes, I get one step closer to that staff oven and creating a full-time position for myself in the company as Top Chef. For now, we will have to keep sampling some fun new foods and developing these products. If you have an idea for a recipe, or have any questions about any of these products or want to know how to get your hands on them, let us know! While we are not actively selling these products, we are interested in developing them.

Feel free to reach out to us to talk about food, beer or anything in between!