In Japan’s past, sushi was primarily known for its light and refreshing taste. Edo-period nigiri sushi centered on toppings like white-fleshed fish (such as hirame) or hikarimono (such as kohada) cured with vinegar or salt, where “freshness” and “clean, light flavors” were prized. Fatty fish spoiled easily and were not particularly favored among Edo diners.
However, as time progressed, food values underwent a significant shift. Advances in refrigeration and freezing technology made it possible to handle fatty fish while keeping them fresh, propelling toro, yellowtail, and salmon to become the stars of sushi. Toro, in particular, was once considered a “discarded part,” but is now celebrated worldwide as the “ultimate flavor.” To modern palates, fatty fish have a “melting richness” reminiscent of marbled beef, and this sensation fuels the popularity of fatty fish.
In recent years, fish such as blackthroat seaperch (nodoguro), splendid alfonsino (kinmedai), broadbanded thornyhead (kichiji), largehead hairtail (tachiuo), bigeyed greeneye (mehikari), and gnomefish (kuromutsu)—once rarely eaten by the public—have gained prominence as premium sushi toppings. These fish are often rich in fat and possess a deep umami flavor, embodying the “richness” and melt-in-the-mouth umami sought by modern palates.
Using fatty fish in sushi demands advanced craftsmanship. For fish like kinmedai and nodoguro, which have beautiful skin, special techniques are needed to highlight the skin’s beauty and the aromatic richness of the fat. Furthermore, to accentuate the natural sweetness in the fat, the temperature and acidity of the shari (vinegared rice), as well as the type of vinegar blend used, are subtly adjusted to balance the umami of the fat with the overall dish.
Through this accumulation of techniques, sushi chefs have refined their skill in “utilizing fat as umami.” Consequently, fatty fish have become not merely “rich ingredients,” but a canvas for the chef’s artistry and skill. Furthermore, modern taste preferences are underpinned by shifts in Japanese dietary habits. Increased consumption of fatty foods like meat and butter, coupled with palates accustomed to processed foods and chemical seasonings, now responds more strongly to rich, fatty, or salty flavors than to subtler tastes. This environment also fuels the growing preference for fatty fish.
Moreover, the influence of media and social networks heightens expectations of deliciousness even before tasting.
Thus, the fatty fish once shunned by Edo-period people now captivates as a “fish representing sushi.” This shift in taste can be seen as a uniquely modern symbol of affluence, born from technological progress and cultural sophistication.