When I first tried sushi in Tokyo in the fall of 1977, I thought of myself as an intrepid culinary adventurer who, if he survived the experience, would return to America to tell the incredible, unbelievable tale of the day he ate raw fish on rice balls. Someday, perhaps, I would tell my children. By the time I returned to the States two years later, I found sushi bars in Midtown Manhattan; within a few years, nigiri sushi became the signature forage of the Young Urban Professional. As for my children, they eat sushi three or four times a week. They developed a taste for it when they were living in Nashville, Tenn., which, though it lacks any convincing French or Italian restaurants, has several fine sushi bars. From very different perspectives, “The Zen of Fish,” by Trevor Corson, and “The Sushi Economy,” by Sasha Issenberg, attempt to account for the transformation of sushi from a provincial street snack to the international luxury cuisine of the 21st century.

Although raw fish is generally the first thing we think of when we think of sushi, it didn’t start out that way. “The Japanese tradition of eating fresh raw fish has nothing to do with sushi,” Corson tells us. “Sushi began as a way of preserving old fish.” Rice farmers in Southeast Asia would pack fish in jars with cooked rice to preserve it. The fermented result tasted more like stinky cheese than like fresh hamachi; the Japanese, in adopting the strategy, gradually shortened the fermentation time, developing a fresher style of sushi that still relied on fermented rice for its distinctive sour taste. This fish, usually carp, was salted and pressed in rice under a stone. Sashimi, in the form of raw fish, was something else again, an aristocratic delicacy little known to the urban masses.

The eureka moment when fresh fish was first squished onto a ball of vinegared rice and eaten on the spot is lost to us, but it happened somewhere in Edo (soon to be Tokyo) during the 19th century. Some hungry soul got tired of waiting for his sushi to ferment. What we now think of as sushi — Edo-mae nigiri — was invented as fast food for laborers, served by outdoor vendors from small carts. Soy sauce was offered, probably to mimic the fermented fish taste of the earlier style. The Tokyo earthquake of 1923 leveled the city and dispersed many of the city’s sushi chefs, who took Tokyo-style nigiri sushi to other parts of the country.

In the mid-1960s a restaurant called Tokyo Kaikan opened one of the first sushi bars in Los Angeles. There, a chef named Ichiro Mashita, unable to find any fresh toro, started substituting creamy avocado for the fatty tuna belly, eventually coming up with the California roll, winning the eternal gratitude of my son Barrett and millions of other gaijin. Los Angeles was the beachhead for the sushi invasion, attracting many Japanese chefs eager to make their fortunes and to circumvent the grueling 10-year apprenticeship required in their homeland. Others followed Japan’s corporate envoys to New York during the boom years of the Japanese economy. In 1983, the New York Times restaurant critic, Mimi Sheraton, awarded four stars to Hatsuhana, a Midtown sushi den — the official imprimatur for the new cuisine.

Trevor Corson’s “Zen of Fish” bounces between Los Angeles and Japan, as he follows the trials of a recent class of the California Sushi Academy, founded in 1998 to train would-be American sushi chefs. It’s a clever narrative strategy — the reader learns the practice and history of sushi alongside the students. On the other hand, his decision to focus on the least promising student — a young woman who is squeamish about touching fish and is afraid of sharp knives — makes for a sometimes frustrating and pedestrian journey. Given Corson’s apparent mastery of Japanese and of original source material, one can only assume the samurai and Zen clichés result from the student’s limited point of view. (“Kate liked Toshi immediately. He was cheerful and stern at the same time, like a monk who was also a kung-fu warrior.”) The monk/warrior head of the academy, Toshi Sugiura, comes across as a colorful if enigmatic character, a profligate party boy and self-appointed guardian of sushi traditions. On the other hand, Corson’s portrait of the American students, as opposed to the glimpses we catch of the single Japanese acolyte, could be used to buttress the view that gaijin in general, and women in particular, don’t have the stuff to make it behind the sushi bar. But hey, somebody’s got to man the counter at all those sushi bars springing up in Oklahoma and Nebraska.

Fortunately, the classroom scenes are intercut with authoritative, often amusing, chapters on sushi history, marine biology and the physiognomy of taste. While the students hack away at mackerel, Corson serves up bite-size explanations of the invention of soy sauce, the sex life of red algae and the importance of umami, that mysterious fifth taste that underlies so much of Eastern cuisine. His chapter on rice, a subject that Americans take for granted, is itself worth the price of the book.