TOKYO — Clad in white chef uniforms and caps, students at the Tokyo Sushi Academy hurriedly shape vinegared rice into “nigiri” sushi with their hands to pass a test requiring them to complete 18 nigiri within three minutes.

After the test, students nervously wait for instructor Suehiko Shimizu to examine the appearance and weight of the nigiri. Each nigiri should weigh 18 grams (0.63 ounces) and some of the students express relief or disappointment as the number of grams is shown on their scales.

Shimizu, who became an instructor after 55 years of working at sushi restaurants, says completing 18 nigiri within three minutes, or making one every 10 seconds, is “the minimum requirement” for a professional sushi chef.

The academy in Tokyo’s Shinjuku district is Japan’s only sushi chef training school that widely accepts both Japanese and non-Japanese, including those who have no experience of sushi-making.

It attracts not only foreigners who want to improve their career prospects in the food service industry by learning sushi-making skills in Japan’s capital, but also Japanese who want a fast-track route to being a sushi chef rather than spending years of apprenticeship at traditional restaurants. The school opened in 2002.

At a Sunday weekly class, Stephen Vannatter, 35, from the United States, struggled to neatly and speedily make nigiri. “This nigiri test is the most difficult part of the class,” said Vannatter in fluent Japanese.

A company worker in Tokyo who has lived in Japan for about 10 years, Vannatter said he is satisfied with the class, where he also learns how to use knives and cut various kinds of fish.

The native of Michigan said he has been enrolled in the weekly sushi class since April to learn techniques “as a hobby,” but that he hopes to work at a sushi restaurant and promote “authentic Japanese food” in the future.

His Japanese classmate from Saitama Prefecture, 38, who declined to be named, shares with Vannatter a passion for promoting “true sushi culture” around the world.

The worker at a metal manufacturing company said he decided to attend the Tokyo Sushi Academy because the school encourages its graduates to work abroad.

“I heard many sushi restaurants nowadays are run by Chinese or Koreans and thought more Japanese should work abroad as sushi chefs,” said the male student, who has a dream of working in Singapore, Australia or southern Europe after fully mastering sushi– making techniques.

He said he chose the academy to sidestep “a feudalistic culture” of training sushi chefs at traditional restaurants, under which it takes a couple of years before apprentices are allowed to even touch fish.

Tony Kobayashi, a Japanese engineer in his 40s, said he dreams of working as a sushi chef seasonally in resort areas along the Aegean Sea or Adriatic Sea after retirement to cater to tourists from around the world.

Kobayashi believes once he masters sushi-making skills, he can continue to work even in his 70s. “It would be better to keep working rather than being in a daze at home,” he said.

Yasunobu Mogi, a Tokyo Sushi Academy official, says the school was established by business consultant Makoto Fukue, who advised aging Japanese sushi restaurant managers troubled by a chronic lack of successors, to quickly train sushi chefs.

So far, more than 1,000 graduates of the school work in more than 30 countries as sushi chefs, instructors, advisors and consultants. In addition to the Sunday weekly classes, the school has one-year sushi chef training courses, eight-week intensive diploma courses and occasional lessons on making decorative sushi rolls.

Many foreigners who stay in Japan on a tourist visa enroll in the eight-week diploma course. Since the tuition is rather expensive at about 840,000 yen (about $10,000), students are mostly from relatively wealthy countries in Europe, North America and Oceania, according to Mogi.

Even though similar sushi schools in California and London offer classes with lower tuition fees, many people choose the Tokyo school.

“Students probably think their career can get a boost if they study authentic sushi making in Tokyo,” Mogi said.

Among Japanese students are children of sushi restaurant managers, those who have lived abroad and aim to promote Japanese sushi culture in the future, and members of the Self-Defense Forces who want to learn sushi-making skills before being dispatched overseas, he said.

About 30 percent of the academy’s students are women. Prejudice against women in traditional Japanese restaurants, where chefs attending at sushi bars have primarily been men, makes it difficult for female chefs to serve in front of customers, according to Mogi.

But there are plenty of job opportunities for them to work in kitchens or overseas restaurants, he said.

According to estimates by vinegar maker Mizkan Group Corp. there are about 30,000 Japanese restaurants abroad, with more than 30 percent of the total operating in the United States.

It is believed that the number of such restaurants will sharply rise in emerging economies such as China and Russia as well as countries in Eastern Europe, South America and Africa.

Tsuyoshi Nagano, a 40-year-old Tokyo Sushi Academy graduate, now lives in Athens and occasionally works as a private sushi chef in the city.

He told Kyodo News in an e-mail interview that the Greek capital has been experiencing a “sushi boom,” with rolls sold in supermarkets and Asian restaurants. But only a few restaurants employ Japanese sushi chefs and the quality of sushi served in other restaurants is very poor, he said.

“Even though sushi has been introduced as a healthy diet, restaurants where no Japanese are working offer dishes using artificially colored roes and frozen ingredients, such as shrimp and eel, to which preservatives and chemical seasonings are added,” he said.

Nagano said he is well aware of the need to cater to preferences of local customers, but that he uses organic rice, imported Japanese “nori” (dried laver seaweed) and self-made soured ginger to serve his customers.