Japanese cuisine often adapts foreign dishes to suit local tastes.

For example, curry, which originated in India, evolved in Japan into “mildly sweet and rich curry rice” thickened with wheat flour roux and served over rice. This is a completely different dish from the low-viscosity Indian curry with its complex spice aromas.

Similarly, Italian carbonara traditionally uses Pecorino Romano cheese and no heavy cream. In Japan, however, heavy cream or milk is often added to make it richer and creamier.

To people in the country of origin, these adaptations might seem unusual or even unacceptable. The same is true for sushi: foreign adaptations can surprise Japanese diners. Yet, I don’t mean to dismiss the practice of adjusting recipes to local tastes. For chefs, it is a natural and creative process.

Traditional nigiri sushi, however, is different. Like changing the rules of a sport, altering its fundamental principles means it can no longer truly be called nigiri sushi.

 

First Principle: Shaping by Hand

While “nigiri” literally means “to grasp,” making nigiri is similar to shaping an onigiri (rice ball). Both involve forming rice by hand into the ideal shape. The outside is pressed firmly to prevent crumbling, while the inside remains light and airy so it easily falls apart in the mouth.

The first principle is simple: nigiri must be made by hand. What robots or machines produce is only “something like” nigiri sushi. True craftsmanship requires human hands.

 

Second Principle: Using Vinegared Rice

The rice used for nigiri sushi is not plain white rice, but rather vinegared rice, called shari. The “su” in “sushi” means vinegar (or sour), which balances the flavor and aroma of the dish.

Without vinegared rice, it cannot truly be considered nigiri sushi. This is the second fundamental principle.

 

Third Principle: The Concept of Sushi Toppings

Sushi toppings originally refer to ingredients prepared and processed by the chef. Seafood is central, but vegetables such as kanpyo (dried gourd strips) and cucumber have been used since ancient times. Other staples include menegi (young green onion shoots) and shiitake mushrooms.

Ingredients like seasoned beef or Chinese-style shark fin, which differ in preparation and flavor from seafood, do not fit within the tradition of nigiri sushi. These belong more naturally in steak houses or izakaya bars.

Fish is best eaten as sashimi immediately after death. Then, after aging for several days, it becomes nigiri sushi. Just before spoiling, it’s eaten grilled or simmered—an ironclad rule of Japanese cuisine. Sushi chefs deliberately start with the freshest state, perform the appropriate preparation (in the culinary world, this means sparing no effort) suited to that seafood, and then wait for the optimal moment to serve it as nigiri sushi. With the rise of affordable conveyor-belt sushi, the term “Edomae sushi” as a marketing term has become much less common. Yet traditional nigiri sushi is, in essence, Edomae sushi itself.

Toppings that rely on commercially processed items—like caviar or pre-seasoned roe—also stray from tradition, as their flavors depend more on the manufacturer than the skill of the chef.

Nigiri sushi is meant to highlight the taste of a single ingredient. Its philosophy differs from French cuisine, which layers flavors for complexity. Garnishes and seasonings—shiso, green onion, ginger, soy sauce, or a pinch of salt—serve only to enhance the topping, not overwhelm it. Simply adding store-bought tobiko, for example, goes against this principle.

 

Requirements for the Finished Product

Finally, the topping must stay firmly on the rice. If a topping is slippery, like octopus or shellfish, chefs use techniques such as securing it with nori or making small incisions. When a topping cannot stay in place, it is formed into gunkan-maki, a style developed to uphold the principles of nigiri sushi.

While broader definitions of sushi may not require all these standards, traditional nigiri sushi adheres to them. This is why its appearance remains consistent across Japanese sushi restaurants. Extravagant decorations, such as gold leaf, may look impressive but stray from the essence of nigiri sushi.

 

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What is Edomae sushi?