During Monday night’s episode of the BBC2 documentary The Honest Supermarket: What’s Really in our Food, dietician Priya Tew and fish scientist Richard Chivers tested ten cod fillets from five different supermarkets in the UK.
Chivers, who has tested fish for supermarkets and suppliers for over 30 years, tested the samples using the industry standard Torry measuring tool - a systematic scoring system which measures the freshness of fish - and ranked them based on taste, smell and appearance.
Of the fillets tested, 30 per cent had gone off and some were believed to be up to 20 days old. Another 20 per cent needed to be eaten by the following day.
During filming, Chivers could be seen spitting out one fillet, which he argued should not have been for sale, and described another as “like chewing cotton wool”.
The programme revealed that there is limited regulations for selling fresh fish and that the supermarkets decide what use by dates to issue – “as long as the fish won’t make you ill."
According to the Food Standards Agency, sellers "must provide information on the type of freezing process that the fish or fishery product has undergone. This must have been provided by the business carrying out the treatment."
Despite the ruling, Chivers – who found the relevant wording about the frozen status of fish on small letters on the reverse of the package – said that supermarkets aren’t required to make the information “very prominent”.
When asked whether the general public had the right idea about what constitutes "fresh" fish, Chivers replied, “Absolutely not.”
Chris Middleton of British Sea Fishing tells The Independent that he wasn’t surprised by the revelations.
“If you know about commercial fishing, you’ll know that larger trawlers have the resources to freeze fish at sea, while smaller operations don’t – they keep it on ice," he adds.
“If a trawler is fishing out at sea for five, six or seven days, the fish is likely to be sitting on ice during that period – and the days can add up."
Middleton continues, stating that once the trawler returns to shore, it’s then transported to a fish auction, before being transported to fishmongers and supermarkets.
He acknowledges that 20 days was at the “extreme” end of the spectrum.
The Independent has contacted Sainsbury’s, Waitrose and ASDA for comment.
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