'Skimpflation' warning as tinned mackerel alternative hits more supermarket shelves

A growing trend of supermarkets selling a cheaper, less nutritious alternative to tinned mackerel is an example of "skimpflation", a consumer group has said.

Princes - which supplies major supermarkets - has substituted the fish for jack mackerel, an entirely different species also being sold by Lidl.

The switch has been spurred by dwindling stocks of Atlantic mackerel after years of overfishing, with its Chilean counterpart more sustainable and a third of the cost.

"It's a real concern when manufacturers quietly downgrade everyday staples like these as shoppers can end up paying the same price for a product that delivers significantly less nutritional quality," Sue Davies, head of food policy at Which?, said.

Jack mackerel contains about half as much omega-3 and around a third as much vitamin B12 as traditional mackerel.

The shift has prompted complaints from some consumers over differences in taste and texture, as well as concerns about how clearly the replacement fish is being labelled.

Princes announced last October , external that it was changing all of its tinned mackerel products to jack mackerel, saying the species meets the Marine Stewardship Council's sustainability standards.

The firm said its jack mackerel products were "clearly identified" and had been introduced following extensive product and consumer testing, describing it as having a "milder flavour and meatier texture".