There is such a bewildering variety of fresh fish available in stores in Japan these days that it’s hard to imagine a time when things were different. But before refrigeration became widespread in the late 1950s, fresh, unprocessed fish was only available to the well-to-do or people living on the coasts. Most of the fish consumed by regular folk living inland was salted, dried, marinated or otherwise preserved.
Of these preserved fish, salted salmon — called shiojake, shiozake or simply jake — is arguably the most popular. It’s one of the most common fillings for onigiri (rice balls); the star of sakeben, a standard bentō variety sold at convenience stores; and makes a frequent appearance as part of a traditional Japanese breakfast.
My grandfather’s family was originally from a coastal village in Niigata Prefecture, and when he was still healthy his relatives would send him a batch of whole, gutted fresh salmon on ice every winter. My grandmother and aunt would then turn them into shiobiki, a highly salted type of shiojake that’s traditional to that part of Niigata. The salmon was heavily salted inside and out, then hung under the eaves for a couple of weeks to allow the moisture to slowly dry off. I still have memories of gazing up at the open mouths of the salmon as they hung upside down.
The result was something so salty that the surface would be white and crystallized, but it was packed with concentrated umami — a perfect accompaniment to a bowl of white rice, and my favorite onigiri filling.
While shiojake has been made for millennia in the Hokuriku and Tohoku regions in northern Honshu, it did not become widely available throughout Japan until the late 19th century, when large salmon fisheries opened up in newly developed Hokkaido. Salt was shipped up to Hokkaido from Shikoku and the treated salmon was carried back south, using the newly established railway system. It became one of the first mass-produced food products, cheap and available year-round.
Shiojake continued to be popular throughout the 20th century, even after the widespread adoption of home refrigerators in the later 1950s made cooking fresh fish at home much more practical. But in the ’70s there was a dip in the fortunes of salted and dried fish (himono) in general as health concerns were raised about the high salt content of the traditional Japanese diet.
As the sales of shiojake that was stiff and white from salt plummeted, producers started to push amashio, or “sweet” (meaning low in salt) shiojake, which often had to be marinated in amino-acid liquid to increase the umami artificially. And in the 1990s the sales of raw salmon, which had previously been thought of as tasting too “fishy,” overtook sales of shiojake for the first time.
Fortunately, shiojake has been making a comeback over the last decade, riding the wave of nostalgia that has revived the popularity of many kinds of “retro” foods. Shiojake is now available in several levels of saltiness: lightly salted amashio, karashio (high-salt) types that bring a tear to the eye, and nakashio between them. Try them all to see which level of saltiness suits you best, although go easy on the karashio ones — a little goes a very long way.