Nukazuke (nuka = rice bran; zuke = pickle) is a type of Japanese pickle, made by fermenting vegetables in a rice bran pickling “bed” (aka nukadoko). Almost any vegetable may be pickled through this technique, though traditional varieties include eggplant, daikon radish, cabbage & cucumber. The taste of nuka pickles can vary from pleasantly tangy to very sour, salty and pungent.
2 lbs dry rice bran
1/2 oz kombu seaweed, cut into smaller pieces
10 small dried chili peppers
1 cup sea salt
1 tbsp yellow mustard powder
6 garlic cloves, sliced
1-inch piece of ginger, minced
about 6.5 cups of water
Time until ready: ~ 6 weeks
In your crock, combine the bran, salt, mustard, seaweed, garlic, ginger, and chiles. Add the water slowly, in 3 batches, as you may not use all the water. Mix the rice bran with your hands as you go. Stop adding water when the mixture has the texture of wet beach sand (suitable for building sandcastles). The texture should be wet and clumping, but not pooling water. Keep the nukadoko (rice bran pickling bed) covered with a loose lid at all times to let CO2 escape but keep out insects and debris. Add a cloth in between the lid and crock if necessary to keep out fruit flies. Store in an accessible location as your nuka bed will need to be turned and aerated daily.
In the beginning, the nukadoko must be primed for optimal fermentation. Prime your pickling bed by immersing vegetable scraps into the bed, covering them completely with bran, and removing them one day later. (While you could eat these priming vegetables, they won’t have a great flavor, so feel free to compost.) Scrape off as much of the rice bran as you can back into the crock before discarding vegetables. If your vegetable scraps are small, tie them up in cheesecloth for easier removal. For at least 2 weeks, but preferably 6 weeks, immerse and discard new vegetables daily, and stir the bed thoroughly, aerating it from top to bottom, then patting down the pickling bed into a smooth surface, being careful to wipe down the sides.
After about 6 weeks, your pickling bed should have fermented nicely with a pleasant, earthy smell and is mature enough for proper pickling. Bury larger chunks of vegetables – for example whole or halved carrots, turnips, or large chunks of daikon radish. For watery vegetables like cucumbers or eggplant, trim and rub with salt to extract water for about an hour. Rinse and pat dry before immersing in the nukadoko. Let vegetables ferment for as little as 8 hours and up to several days or weeks to take on the flavor of the bed. Remove the vegetables, keeping as much of the bran as possible in the crock. Rinse off any remaining nuka (if desired), pat dry, and cut into small pieces to serve.
Your nuka bed will continue to need to be stirred by hand daily. If you need to go out of town, give a thorough stir and transfer entire mixture into a Tupperware-style container, cover tightly, and store in the refrigerator until you’re ready to return to daily stirring maintenance. Consider adding more rice bran and seasonings for greater depth or when bed inevitably reduces in size.
Making sure the nukadoko maintains the right level of moisture and cool temperature is crucial. With proper care, this bed can be used indefinitely. However, if you don’t stir daily, or if the weather turns quite warm, or if your nukadoko gets too wet, the contents could take on a funky sour smell or grow moldy. If this happens, there are several things you can try to revive the bed: Remove the mold. Transfer the contents into another container and clean crock thoroughly. Build up the nuka by adding ¼ cup additional mustard powder, 1 ½ cups new rice bran, and another ⅓ cup salt. Mix it in completely and let it dry out, uncovered, in the refrigerator or in bright sunlight, 24-48 hours, stirring it very well to aerate it, top to bottom, 3-4 times per day. Resume aforementioned pickling rituals.
Recipe adapted from Asian Pickles by Karen Solomon.