WHAT IS KOJI?



If you have been following Reed & Co for a while, you will know that we love Koji. For some time, we have been making our own koji and even had a pop-up restaurant Koji Bird at the distillery, to celebrate all that is great about Koji. Then of course we have our Koji Spirits, our Japanese influenced spirits that feature Koji…but you might still be wondering...

What is koji?


Here are some of the basics to get you up to speed.


KOJI IS A MOULD


Koji is otherwise known by its scientific name Aspergillus Oryzae. Aspergillus Oryzae, is a mould in the fungus family in the genus Aspergillus and it is used in fermentation.

Only a few very specific isolated species out of hundreds in the genus aspergillus can be used for Koji.


IT IS THE NATIONAL FUNGUS OF JAPAN


It has been used by the Japanese, Chinese & Korean in food preparation for thousands of years. However, it is primarily known for its use in many traditional Japanese foods.

In 2006, the Brewing Society of Japan designated koji as "a valuable asset carefully nurtured and used by our ancestors," and certified koji as Japan's "national mould".


HOW DOES A MOULD BECOME KOJI?


The Aspergillus oryzae is used for its transformative powers.

It is a filamentous mould when grown on starch grains (primarily rice and barley) generates a powerhouse of enzymes. It turns complex carbohydrates into amino acids and sugars via enzymes it produces to feed itself.


COMMON USES FOR KOJI


Koji is used in the production process of soy sauce, miso, rice vinegar and fermented pastes. As well as alcoholic beverages like sake, shochu, mirin awamori & amazake.



REED & CO KOJI


Our hospitality background as chefs who have lived and worked in Japan led us to a love of koji and an appreciation for the tradition and science of making Koji. We cultivate our own Koji onsite in the distillery which requires strict attention to temperature, humidity, and grain texture. It starts as a spore, and we inoculate the grains and monitor the growth of the filaments (multicellular organisms) which grow over the starch grain to start enzyme production. Enzymes act as catalysts to bring about specific biochemical reactions. It is through these interactions with the grain & starches that the first fermentation takes place, providing a rich flavour base for our Shochu long ferment and then distillation.


Koji is used in our Koji Spirits Yuzushu & Spirit Lab Chilli Koji both available in our distillery and online store.