Workshop: Reduce food waste with the Nukazuke fermentation method

As part of the Green Conference 2022 HakkoBako and FoodCraft teamed up to host a Nukazuke fermentation workshop. 

Lead by Chef Shima Shimizu we learnt how to use the Japanese method of Nukazuke fermentation to transform food waste using a cultured bed of nuka (rice bran). 

Every kitchen should have a Nuka-Doko (nuka bed) since it’s an easy and low effort way to transform food waste in delicious ingredients that can be stored for a long time. 

Nukazuke fermentation in the HakkoBako chamber @ 25°C (77°F)

One of the great things about Nukazuke is that unlike most other forms of fermentation that require fresh ingredients, with Nuka method you can save those food scraps that are going dry and wrinkly in the back of your fridge. 

Chef Shima showing firm tofu fermented in Nuka-doko

Nuka is rice bran and is the outer part of rice that itself often otherwise treated as food waste. 

To inoculate the nuka Shima showed us how to start the culture by infusing the rice bran with salt, beer, water, kombu, garlic, chilies and dried mushrooms. Other scrap vegetables trimmings such as celery peels and roots were also added into the nuka bed. These ingredients will introduce the right microbes into the Nuka and sets the flavour profile of your bed. After one week the bed will be ready to use for pickling.

Shima amazed us during the workshop by pulling out a range of mystery ingredients from her nuka. Starting with carrots, turnips, daikon radish, broccolini before shocking us with a huge watermelon radish, hardboiled eggs and a large piece of firm tofu. 

Fermented Watermelon Radish

Just like all living things each nuka bed will be unique in the flavours it produces, the speed of which if ferments depending on the temperature you set and what ingredients have previously been fermented in the bed. 

For further exploration Shima mentioned other husks may be used instead of rice bran, for example wheat husks, coffee chaff or other ingredients with similar characteristics to rice bran.