Homegrown Shoyu Co is a small-batch fermentary run by chef Oliver Edwards.

Edwards is the co-head chef (with his wife Brianna Smith) at Bar Merenda in Daylesford, and the pair previously ran the kitchens at Hazel in Melbourne and The Summertown Aristologist in the Adelaide Hills. Born out of lockdown experimentation, this Homegrown Shoyu side-project makes small batches of handcrafted koji-driven ferments. They’ve just released their first product: a mushroom shoyu made with mushrooms that otherwise would have gone to waste during Melbourne’s lockdowns.

What is Homegrown Shoyu?
Essentially it’s Japanese-style soy sauce made using great local ingredients. It’s a long, slow process, but a satisfying one.

Who are you and what are you all about?
I’m a chef who loves DIY everything – sourdough, cheesemaking, charcuterie, fermenting – you name it. During lockdowns I became a bit obsessive about growing koji, the powerhouse mould that creates soy sauce, miso, sake and other wonderful foodstuffs. It felt like peak fermentation/experimentation, and the experiments got progressively bigger and better. Before I knew it, I’d converted the spare room to grow mould in, there was a row of 200-litre barrels of shoyu in the backyard, and my wife was asking pointed questions about my future intentions for the project… so Homegrown Shoyu Co was born.

How do you make it?
I grow mould on soybeans and wheat and then cover these with salty water. Simple!

If I can elaborate, I grow koji on biodynamic soybeans and wheat, before combining this with brine and mushrooms or other ingredients. Then it’s a waiting game. Over time enzymes from the koji break the proteins down into amino acids, including glutamate – that’s the savoury umami yummy rich flavour that’s central to soy sauce.

With our mushroom shoyu, a huge amount (hundreds of kilos!) of mushrooms went into the base pre-ferment. They’re not just a later flavour addition – they were integral to the ferment too and were broken down by the koji to contribute heaps of flavour to the sauce. 

What excites you about this project?
Every part of the process is exciting, but the heart of it all is growing great koji. It’s exciting to do this using great Australian ingredients that are well farmed – I’m using biodynamic dry-grown soybeans, biodynamic heritage ‘Zanzibar’ red wheat, and amazing mushrooms from Unearthed in the Dandenong Ranges. Koji is also a great way to unlock the potential of foods that might otherwise have gone to waste – our mushroom shoyu is made with mushrooms that were otherwise destined for compost when lockdowns hit and Unearthed lost their restaurant customers overnight.

What are the perfect conditions to enjoy Homegrown Shoyu?
It’s quite delicious in most conditions. Splash it on everything. We’re using this as a finishing soy to dress raw or cooked seafood, vegetables, or meats. Right now, we’re loving it on spring veg like stir-fried or steamed asparagus, snow peas and sugarloaf cabbage. We’re also using it last-minute to season broths – ramen, pho, chicken noodle soup, it can jazz ’em all. Or double down and use it to season mushrooms for the ultimate in savoury, mushroomy goodness. As you can see, we think it’s good on everything. I just need someone to make a cocktail with it to really complete the package – any takers?

Is it here for a good time or a long time?
We’re making single barrels of interesting shoyus, so when they’re gone, they’re gone. At the moment we have a two-year-old mushroom shoyu in bottle. There’s a barrel nearly ready that was made with loads of wakame that was picked by hand from Port Phillip Bay that we’re really excited about. It will be getting pressed soon. 

Where can I buy it?
You can jump on our website homegrownshoyu.com.au to place an order. We also have a few stockists, with more on the way. You can find it at Georgie’s Harvest (South Melbourne Market), Pike’s Mushrooms (Prahran Market) and The Leaf Store. 

Homegrown Shoyu, $24 for 200ml, available at homegrownshoyu.com, @homegrown_shoyu