I think my first real awareness of Japanese pickles was the first time I watched "Tampopo." It would be some time later before I realized the pickles that Tampopo pulled from that 'flowerpot full of dirt' or whatever similar muck I thought at the time were such an amazing Japanese diet staple. All in good time, right?
Nukazuke are incredibly easy to make. I have had a growing fascination with fermentation for a while now. Both Chef K and I have had this interest from home-brewing beers to making vinegar from mother culture to the wonderful world of pickles. Curing hams and other pork parts also falls into this arena. As a kid, I would drink the storebought dill pickle juice in my grandmother's refrigerator (and was repeatedly warned that it would 'thin out my blood' whatever the hell that meant). Besides the great taste of pickles, it is only recently that I have come to understand their great importance to our metabolism.
"Wild Fermentation" If you have not read this book, I highly encourage it ($9 on Kindle). While not the most definitive or detailed tome on pickling, it definitely sparks the bug to pickle. It isn't backed up by any reports or scientific evidence, but the book has captivated my attention and kept me reading more than any other book in quite some time. It opens up the window to a big world full of microbes that are far more important to us than one would imagine. We are so caught up in our modern world of anti-bacterial everything that we are on a path to destroying all of the good little bugs that help us simply because of our lack of understanding. Not that I would throw sanitation out the window, but we are too obsessed with destroying everything under the microscope. We really don't fully understand the complex relationships our bodies have with our little friends. That realization has led me to making and eating pickles everyday.
Making nukazuke is one of the easiest ways to make and eat pickles daily. The rate of reward is very short. Once the nukadoko (fermented rice bran bed) is established, vegetables dropped into the bed are transformed into flavorful pickles in about 24 hours.
Chef K had begun a nukadoko a few months back, but lost it. The nukadoko is similar to a sourdough starter culture in that it is alive and needs to be monitored and fed. Using it daily is a simple way to keep it going. I have started another culture since and it's thriving. Supposedly, there are family nukadoko cultures in Japan that are passed from generation to generation. If not maintained regularly, rendering it dormant (through refrigeration) may be necessary to preserve it.
The most stressful part of the nukadoko so far has been getting it going. The key elements that are combined are toasted rice bran, brine, miso, beer, aromatic vegetables (ginger, radish, cabbage), and time and attention. It will take about a week and a half to get it where you want it. In that time, it is best to keep the nukadoko weighted (so the brine extends above the bran) and covered with cheesecloth. It needs to be fed daily. At this stage, the vegetables inserted are mainly to flavor the nukadoko and to get the natural fermentation going. I tasted these everyday after removing them, noticing the slow transformation day by day. Once established, weighting it is not necessary... just keep it covered with cheesecloth, stir it up daily, and feed it... this time harvesting the vegetables afterward as pickles.
The nukadoko itself resembles wet sand and smells of fermenting bread dough and koji. It should be tasted regularly for saltiness (if the salinity drops too much, the opportunity for bad bacteria to move in and thrive increases). If the bed begins to smell overly sour or putrid, then it is probably bad. Otherwise, keep on pickling and eating.
More on pickles...
Another pickling device that both Chef K and I have invested in is the pickle press. This is another quick way to create tsukamono type pickles with quick turnover. When using with an acidic brine (with vinegar), the press is great for non-fermented pickles... but still highly enjoyable. I've also made several batches of brine-fermented pickles recently when coming across fresh vegetables prime for pickling at the farmers' market or otherwise. These involve a bit more time and trust. I say trust because the brine will develop quite a garden of colorful molds on top. This is part of the beauty of pickling because it can be different each time and it's like pulling a slot machine of pickle flavor. The last batch has the flavor of lightly sea salted oysters (these were refrigerated in fresh brine and I am still enjoying them). I've managed to get the salt level as low as 3% during fermentation without letting any 'bad' bacteria thrive. Another big benefit of fermentation is increased umami.
After making these pickles a part of my everyday diet, I've noticed that my digestion is a little more at ease. Like many chefs, I have a horrible diet and often eat very late at night. As I get older, it has wreaked havoc on my metabolism. I've tried omeprezole for a while, but don't like depending on medication... besides, they never worked that well and I still suffered. On the pickle diet, my system is much more balanced and at ease. I simply feel better. Just like "Wild Fermentation," I cannot back this up with scientific data and have no detailed reports to reference. It just works for me. Fermentation is like cooking with microbes, and just gives us chefs a whole new world to explore and learn in. Catching spores from the air and building cultures is like foraging and gardening on a microscopic level.