Similar campaigns to certify authentic sushi overseas have been criticised as an attempt to impose a “sushi police”, but the All-Japan Sushi Federation says the latest effort is aimed at promoting hygiene.

“Most restaurants overseas make sushi dishes in the same kitchen as those preparing meat,” said Masayoshi Kazato, a leading sushi chef who has devised the certification system.

“It gets unhygienic if you deal with raw salt-water fish in a kitchen without water running constantly for cleaning,” he said.

The group, which represents sushi restaurants in Japan, plans to hold its first seminar in Singapore January 26-27 with similar seminars to be held in London, Los Angles and San Francisco next year.

There is a mounting concern among sushi chefs in Japan that, if food poisoning repeatedly occurs in the world because of a lack of proper knowledge and techniques, sushi may get branded as dangerous food, Kazato said.

“Japan created sushi 200 years ago to eat raw fish deliciously and safely when they did not have a refrigerator,” he said. “I want professional chefs to know how much knowledge is needed if they want to serve raw fish.”