Countdown supermarket is defending itself against claims the company is dumping tonnes of fish, including snapper.
A report by Native Affairs on Maori Television suggests large bins of whole fish were found at a Waikato waste meat processing plant in January this year.
Labour MP Shane Jones, who triggered a Commerce Commission inquiry into Countdown's strategies with its suppliers, is questioning why so much fish is being dumped.
Countdown is owned by Progressive Enterprises, and its general manager of strategy Richard Manaton told Radio New Zealand's Checkpoint programme on Monday the amount of fish waste is very low.
Mr Manaton said only five tonnes of whole fish was sent to the plant out of a total of 2500 tonnes processed by the company in 2013. He said the waste fish could not be processed because it was unfit for human consumption.