[Gut Health and Pickles]

“Gut health” refers to habits that improve the balance of gut flora by increasing beneficial bacteria. It is expected to boost immunity, promote metabolism, and maintain mental health through the brain-gut connection. This trend has gained popularity in recent years, with the mainstream approach combining probiotics (lactic acid bacteria) and prebiotics (dietary fiber). Among these, pickles—a staple of Japanese cuisine for centuries—are gaining attention as an ideal gut health food, providing both plant-based lactic acid bacteria and fiber simultaneously.

A major appeal of pickles is their rich content of plant-based lactic acid bacteria. These bacteria naturally exist on vegetable surfaces and multiply during fermentation. Resistant to stomach acid, they are more likely to reach the intestines alive. They are expected to support beneficial bacteria in the gut and help regulate the intestinal environment. Additionally, butyric acid bacteria, one type of beneficial bacteria, produce butyric acid—a short-chain fatty acid. By maintaining a slightly acidic environment in the intestines, they play a crucial role in balancing the gut environment. Nukazuke, in particular, is a fermented food where diverse microorganisms like lactic acid bacteria, yeast, and butyric acid bacteria coexist, making it highly effective for supporting intestinal health. However, it tends to be high in salt, so moderation is advised.

Pickles possess distinct characteristics depending on the type. Nukazuke is rich in B vitamins, while kasuzuke is notable for its high content of organic acids and anti-inflammatory compounds. Non-fermented asazuke pickles are appealing for being low in calories and offering an easy way to consume vegetable nutrients. Pickles have long been cherished as a health food. They are thought to have been particularly effective in preventing beriberi, a disease attributed to vitamin deficiency, during the Edo period. Even today, the lactic acid bacteria and vitamins in pickles are gaining attention for their role in supporting immunity.

The spread of pickles in Japan has roots in Buddhist culinary culture. During the Nara period, temples valued salt-preserved melons and eggplants for their excellent preservation and nutrition within vegetarian cuisine that avoided meat and fish. Later, pickling merged with fermentation culture to evolve uniquely. In the early Edo period, the monk Takuan Soho developed pickles by adding rice bran and sweet persimmons to salted daikon radish, enhancing both flavor and preservation. This is considered the prototype of today's “takuan pickles.” Pickling techniques diversified over time. Starting with salt preservation, kasuzuke pickles using koji and sake lees emerged during the Muromachi period. In the Edo period, with the spread of white rice, nukazuke pickles using rice bran became common in households. As a way to supplement nutrients often lacking in a white rice-centered diet, pickles became an indispensable part of daily life. The flavor of each household's nuka bed was passed down, and sometimes even brought as part of a bride's dowry.

Recently, I tried making takuan myself. It started because I struggled to use up a whole daikon radish and wanted to find a way to utilize it. It was also then that I learned takuan is a type of nukazuke. The method is surprisingly simple: just dry the daikon for about a week, then pickle it with rice bran, salt, persimmon peel, and chili peppers. The fact that it can be made without additives is also reassuring. Tasting authentic takuan after so long brought back memories of eating it over rice as ochazuke when I was little. Since I made a large batch, I plan to use any pieces that become overly pickled in fried rice, potato salad, or Korean-style rice balls called chumoppa.

Noda Horo's Rectangle Deep LL
https://www.shokunin.com/en/noda/
Shirokiya Shikkiten's Teshiozara
https://www.shokunin.com/en/shirokiya/teshio.html
Ichiyougama's Kobachi
https://www.shokunin.com/en/ichiyou/kobachi.html

References
https://www2.hosp.med.tottori-u.ac.jp/kanijiru/backnumber/vol7/special/30364.html
https://www.yaegaki.co.jp/bio/column/4191/
https://www.weblio.jp/content/腸内フローラ
https://ja.wikipedia.org/wiki/漬物
https://ja.wikipedia.org/wiki/糠漬け
https://vegetable.alic.go.jp/yasaijoho/wadai/2006_wadai.html
https://mizutamari-shokuhin.jp/takuan/history.html