WHAT IS KOJI
Koji rice is a mold-inoculated rice (koji being the name of the mold, known as Aspergillus oryzae) that is the precursor ingredient to a whole host of Japan’s most popular foodstuffs, such as soya sauce, miso soup, mirin, and sake. It is responsible lending a unique and undeniable umami flavour.
To hear some chefs talk about koji, Cook's Illustrated editor in chief Dan Souza says koji is "one of the coolest, most functional ingredients out there." Noma chef René Redzepi and fermentation-lab head David Zilber, co-authors of the Noma Guide to Fermentation, call it "indistinguishable from magic."
When the cereal is cultured by Koji mold, it produces many kinds of enzymes such as amylase and protease. Those enzymes are the key to transform the starch in cereal into sugar as well as dissolving the protein to amino acid (which is called "Umami" in Japanese.)
THE BENEFIT OF KOJI
1.Koji enzyme helps digestion
As you see above, Koji contains many kinds of enzymes, and those enzymes dissolve starch and protein. After all, it helps digestion and absorption of nutrients, your body efficiently ingest the nutrients of the foods.
As a result, it improves your gastrointestinal function by smooth digestion.
3.Recovering from fatigue
As it's mentioned in No.2, Koji produces vitamin B2 and B6. Those vitamins are helping to recover from fatigue.
In addition, Koji breaks down starch into glucose, glucose
is the most popular nutritional support for recovering your energy.
2.Produce multiple vitamins
Koji works actively under the certain temperature (the most active temperature is around 30-40℃ which is almost same as our body temperature). When it's active, it produces multiple vitamins such as vitamin B2, B6 and niacins. Those vitamins are well known for improving your skin turnover.
Oligosaccharides is one of the sugar which is also produced by dissolving from starch. Oligosaccharides plays an role to improve the intestinal environment since Oligosaccharides activate probiotics in your intestine.
Koji is not eaten on its own, but when the food is cooked/marinated with koji rice, the koji enzyme helps to bring out the flavor of food and improve the tenderness of meat.
1. Koji Rice/Barley Koji
Make homemade miso or brew sake at you home.
Here is the recipe for DIY Miso Making!
You can even make your own Shio koji/Shoyu koji with rice/barley koji.
Here is the instruction for fermenting Shio/Shoyu koji!
3. Shoyu (soya sauce) Koji
Shoyu koji also can be an all-purpose seasoning like shio koji. It can be marinated with meat/fish, or simply poured onto meat, fish or vegetable as a finishing. It's almost between shoyu (soya sauce) and miso, but richer in flavour. It can also be used in place of soya sauce. Recipe ideas
2. Shio (salt) Koji
Shio koji is a natural seasoning used in Japanese cooking, one of the most trendy and popular ingredient in Japan. Marinate meat/fish with shio koji, then the enzymes in the shio koji break down proteins to elevate umami flavors as well as contributing to tenderizing meat and fish.
Simply use shio koji as a substitute for salt in your cooking to boost umami up! Recipe ideas
Amazake is a popular Japanese hot drink for occasional events like New Year. Literally means “sweet” (甘) “sake” (酒), but usually non-alcoholic drink made with koji rice. Under the fermentation process, the enzyme of koji rice dissolves the starch in the rice and transform to sugar. (The sweetness derives from rice.)
Nowadays, Amazake is getting attention as a great substitute for sugar, especially for vegan baking.