What the hell is Koji?

There are so many new trends and buzz words out there at the moment when it comes to food and so called “super foods”. One of them you may have heard of is Koji. And no, we’re not becoming confused with Goji. 

Koji is a word which pops up a lot when it comes to Japanese cooking, and is used to make things like soya sauce, miso, mirin and sake. Even though the word may be new to some, it’s an ingredient which has been used in Asia for centuries to add a flavour and help with Japanese wine-making. 

There are a few misconceptions surrounding what Koji actually is. Is it a yeast? Is it a mould? No, in fact it is made from rice and/or soya beans which have been exposed to a fermentation culture called Aspergillus oryzae. (I know you’ll remember that for your next argument with your family when protecting your decision to serve them up some koji miso!)

The culture Aspergillus oryzae is a naturally occurring culture which is quite common in Japan, where it is known as ‘koji-kin’. 

So... koji must be created. It is created by adding this particular culture to steamed rice or soya beans and kept in a warm and humid place in wooden trays for nearly 50 hours. Over these hours, the culture feeds on the rice or soya beans, thereby breaking them down and becoming ready to use in the creation of things like Japanese rice wine or other scrumptious flavours.  
Japanese looking food steaming
Koji acts to release amino acids, fatty acids and simple sugars which can help to increase flavour and depth of food. 

So are there any health benefits to Koji or is it all just for taste? Conclusive research is pretty limited, so the short answer is: it’s hard to know. But there is a chance we might one day realise that Koji helps to increase the bio-availability of nutrients we need to absorb. In other words, it might help us get more of the good stuff out of the food we eat and into our system. But in order to know for sure, there definitely needs to be more evidence, so keep your eyes peeled for any new studies popping up in the future! 

So there you go… a little insight into the magic that happens both before and after enjoying that sake, or two, or three!
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