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2 Mad Doctors


1 secret recipe

The Original MOULD Fermented Koji Sauce

Dip - Liven up your food by using Koji Kins as a sauce on the plate

Marinade - Bring depth to your food by adding Koji Kins 30 mins before and leaving in a warm place

Cure -  Bring the best out of your ingredients and cure with Koji Kins for up to 12 hours in the fridge to unlock the hidden flavours within!

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[hyi] is hawt!

Our Koji have munched up these chillis and released their undercover fruity notes! Watermelon on the nose, pineapple on the palate? Yup, we get those too. 

Level up your brekkie or impress diners with tangy & hot Bánh mì.

Ingredients (allergens in bold)—Chillis, Rice Koji, Sesame Seeds, Shallots, Garlic, Maple Syrup, Rice Vinegar, Sea Salt, Spices, Probiotic Live Cultures.


[yami] is dark

a sticky umami tribute to the BBQ sauces of old. With a big Koji twist, that is. 

Dunk in chips for umami greatness, or marinade pulled jackfruit for a banging burger!

Ingredients (allergens in bold)—Maple Syrup, Rice Vinegar, Rice Koji, Sesame Seeds, Chillis, Garlic, Sea Salt, Spices, Black Truffle, Saffron, Smoke, Probiotic Live Cultures.

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[Shio] is ancient 

We don’t reinvent the wheel at Koji Kins. We strap a jetpack to it. Marinade veg or, if it’s your thing, meat (shhh), and let the sauce transform them into delicious and free amino acids.





koji is a magical mould


It has been used for thousands of years in Japan to make soy sauce, miso and sake. It has a secret ability to transform proteins, making them deeper in flavour and absolutely delicious.


We have bundled these secrets into our probiotic, vegan and gluten-free sauces - use them to dip, marinade, cure… or, just have a shot neat from the cap. This is the way.


What you see is what you get. All our ingredients are 100% natural with no additives, colourings, sweeteners or emulsifiers.

Green & Clean

All our sauces are 100% plant-based. No ifs, no buts.

friendly bugs

We care about your microbiome and our experiences as doctors and nutritional scientists reinforce this. Koji Kins is a lively prebiotic and probiotic and is full of life. Enjoy it with a healthy and predominantly plant-based diet - treat yo’self.

(Re)use me, ‘til you use me up

We have designed our bottles so that you can re-use them to ferment your own sauces! In fact, if you do it as soon as you finish our sauces, the friendly bugs and Koji Kins left in the bottle will jumpstart the process! Find our suggested recipes here soon. We’d be delighted if you can make a better sauce!


the way

Koji is a mysterious thing, but we have managed to harness its powers in our special mould-fermentation recipe to bring you our original Koji Sauces!

Dry Fermentation is when our Koji spores meet rice and begin to grow. Kept at a precise temperature for 42 hours, Koji finds a new home within the grains of our rice. At this point Koji is pearly white, has a soft smell of honeysuckle and a hearty rice pudding flavour.

Enzymatic Fermentation is when we really turn it up to 11. Our Koji Kins are mixed into our top secret recipe and enzymes break down proteins into free amino acids and create natural sugars. The Maillard reaction takes hold, creating complex sweetness and that dark umami flavour we love. Colours darken with a smell like freshly roasted coffee and a deep peanut butter and miso flavour emerges.

Lacto-Fermentation is when friendly Lactobacilli join the party. Alright alright alright! The sauces begin to bubble away, bringing tanginess and fruit flavours that round off the lively flavour of Koji Kins. This can keep going on in the bottle slowly for several months - it only gets better!


You really should keep this to yourself, though.


two mad doctors

Every doctor learns about benevolent bugs and friendly fungi. Only truly mad doctors harness these congenial citizens to make such delicious sauces.


Ramy and Victor have been inoculating inklings, bubbling brainwaves and on fermenting follies for many years to bring you Koji Kins - a genuinely unique sauce. Taking some snippets of science, a few ancient traditions and a pinch of ingenuity, we have given this fun-guy (sorrynotsorry) a new lease on life.


We hope you love these sauces as much as we love making them!


the future is brewing

Not all Koji wear capes… If you’ve gotten this far, you probably can see why we think Koji will save the world.


If we can use Koji Kins to make veggies taste bright and deep, that just might nudge people to reduce their meat consumption - it’s certainly helped us! 100% plant-based, all natural and in reusable bottles, we hope that you join our Koji journey to make the world a better, more mycelial place.


Orders currently live in online store!

Sign up to be a Kin and get 20% off your first order!

You can also find us on the shelves in Hove, click here to find out more.


Seen in the wild


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on the grapevine

See our feature in Brightontheinside

all ears

Ideas? Inspirations? Experiments? We’d love to hear from you.



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