Seafood lovers may be fishing for answers after a study by University of Guelph researchers suggests fish is being mislabeled at more than one point in Canada's supply chain.

Bob Hanner, an associate professor in the department of integrative biology at the U of G says researchers found mislabelling was compounding at each stage of the supply chain.

"Nearly 20 per cent of the samples being imported into Canada were mislabelled," said Hanner.

"At the wholesale and processor level that was closer to 30 per cent. And then at the retail level closer to 40 per cent."

Hanner and the University worked with the Canadian Food Inspection Agency to collect 203 samples from 12 species of fish. Researchers used DNA bar coding to determine the species.

Fraud or honest mistake?

The misidentification is bit of both human error and fraud, said Hanner.

Anyone buying fish that has already been skinned and processed may not know the difference, as some seafood is hard to tell apart.

"So we do see evidence of low value commodities being substituted for a species of a higher market value," Hanner said.

"Things like farmed tilapia being sold as red snapper, farmed salmon being sold as wild Pacific salmon."

Hanner says if mislabelling happens in error, consumers could sometimes also be getting more expensive fish at a cheaper price. However, he said there's no evidence that ever happens.

Barcode solution

In the decade he has been documenting seafood fraud Hanner said the focus was on the consumer and retailer, but until this study researchers never knew which level along the supply chain the mislabelling was occurring.

Researchers want to see Canada move to a similar system used in Europe where the scientific Latin name of the genus and species is placed on the label.

A DNA test would make it easy to determine if the fish is actually what the retail label indicates.

That also means testing should be done at different points along the journey from processing to consumer in order to determine where the mislabelling occurred

Ask questions

Until that happens, Hanner suggests consumers ask question of retailers and food service establishments about what they're eating.

"Where the fish came from; what species is it? I think are good questions," said Hanner.

Alternatively, consumers could buy the product earlier in the process. "Buy less processed products. You know if you buy it with the head on or catch it yourself you're a lot more likely to get what you're paying for."