Sheffield University is rolling out training for students on “micro-aggressions” such as asking Japanese students about sushi and confusing banana with plantain.

The Russell Group institution said that it wanted students to challenge “subtle but offensive comments” directed at their black, Asian and minority ethnic peers.

The university pointed to examples of micro-aggressions that were highlighted by the student union campaign such as asking “Why are you frying a banana?” when it is in fact plantain and saying “That raw fish stuff… Japanese culture is weird”.

Other examples include asking “how many times do you wash your hair a week?” and touching people’s hair without their consent.

Sheffield University will train students to become “Race Equality Champions” who will host discussion sessions about how to spot and contest micro-aggressions.

Last year, Sheffield student's union was criticised for after it announcing that it planned to hold focus groups on racism, with white undergraduates banned from attending.

They said they wanted the university to change from being “simply non-racist to actively anti-racist”, but the discussions were only open to “students who identify as black, Asian and minority ethnic”.

Professor Koen Lamberts, president and vice-Chancellor of Sheffield University, said: “We think it's important to be open and honest about racism, which is why we listened to our students and worked closely with our Students' Union and our BME committee to develop the Race Equality Champion roles to change the way people think about racism.