Supermarket fish may be labelled as 'fresh', but it could be more than 14 days old. The rules mean that as long as the fish has been stored on ice since it was caught (but not deep frozen), it can be sold as fresh for up to 15 days. One food scientist bought and tested 14 pieces of fish from British supermarkets, and discovered that a third of it was between 12 and 15 days old.
Food scientist Richard Chivers carried out an investigation for the Sunday Mirror, on fillets from Tesco, Asda, Sainsbury's, Morrisons and an independent fishmonger, The fillets were tested raw, then cooked for two minutes in the microwave and tasted.
Chivers said that a third were on the brink of the limit, while three samples were nine-12 days old and the rest were between six and nine days old. The supermarkets told the newspaper, that the fish on the shelves was of high quality, and that labelling was clear.
This reflects the findings of a very similar study conducted last year - where a third were assessed as being more than ten days out of the water. The expert in this case used another small sample of products to create a snapshot, but said she was disappointed with the taste of the fish that had been out of the sea for longer.
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Should we be worried?
None of the samples tested in either case was off, and none would have made anyone ill. They all fell within the guidelines suggested by the Food Standards Agency, so were safe to eat. However, some may have had a relatively short fridge-life once you got them home, and those who had been out of the water for a significant length of time were less likely to taste good.
The good news is that the rules surrounding fresh fish are changing. From December 13, labelling will have to show where and how the fish was caught, and whether it has been defrosted. It will mean you can tell at a glance how long it has been since the fish was in the water.
In the interim, it's important to remember that it's not necessarily the end of the world if our food doesn't make it from farm or sea to the table in a matter of a few days. Pricey aged meat is actually sold on the basis of how long it has been left to mature, while New Zealand lamb is frozen in order to be brought to the UK, so will be six weeks old by the time it makes it to the supermarket.
The same goes for some vegetables. Potatoes and apples are regularly stored for six months before hitting the shelves (the apples will be shipped in refrigerated containers).
But what do you think? Would you be put off if you saw fresh fish that had been out of the water for more than a week?
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