Investigations by the Fair Work Ombudsman have revealed the Nepalese student was paid an illegal flat rate as low as $12 an hour at the takeaway salad and sandwich store Health Express. She said the owner, Jeffrey Herscu, had "made it clear" this was because she was from overseas.

"When I came for the interview, he said that I will give you the job, but as you are not an Aussie, I will be paying you a lesser amount," the student said in a recorded interview with the Fair Work Ombudsman.

"It was really embarrassing for me ... I had Australian friends who were doing the same kind of work, but were getting paid over $20 an hour."

The student, a casual employee, was short-changed more than $23,500 between September 2013 and March last year.

And the Indian student, 31, was underpaid more than $27,300 after receiving flat rate wages as low as $16 an hour.