Why does fish taste so exceptionally good when eaten in a coastal town? There is nothing quite like the experience of enjoying fish that has just been caught, filleted on the spot, and served raw or grilled. That crisp texture and pristine flavor are privileges reserved for dining right by the ocean.
But have you heard of “Jukusei” (Fish Aging)? While dry-aged beef is famous worldwide, fish can also undergo an aging process that dramatically transforms its flavor. Many high-end sushi restaurants conduct their own extensive research to master this technique.
So, what exactly is aging? Simply put, it is a method of breaking down the fish’s proteins into amino acids to draw out deep umami flavors.
While methods vary from chef to chef, “Dry Aging” is one of the most prominent techniques. It typically begins with thorough blood removal (ikejime), often using larger fish. The fish is placed in a refrigerator, exposed to circulating air for several days. Over time, the surface dries out and oxidizes (it may even look spoiled to the untrained eye). However, once this outer layer is trimmed away, it reveals the gem inside: fish with a concentrated, intense umami flavor. By removing blood and moisture, chefs prevent rot while allowing the fish to reach its peak flavor potential.
Many sushi restaurants in Tokyo source their fish from the Toyosu Market. While the quality is undeniably world-class, they cannot physically compete with the absolute freshness of a seaside town where the fish was caught minutes ago. However, this is exactly why Tokyo sushi chefs are so compatible with aging techniques. They turn the logistics into an advantage, using time and skill to create a delicacy that exists in a completely different dimension from fresh fish.
The crisp, firm texture of “Fresh Sushi.” The rich, creamy umami of “Aged Sushi.”
Tell me, which one is your favorite?
For an authentic Tokyo omakase experience, visit Sushi Shutatsu in Ogikubo.
Enjoy Edo-style craftsmanship, Toyosu’s finest seafood, and genuine Japanese hospitality.e true taste of Tokyo sushi.
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