Officials in Ireland have pointed to Polish meat ingredients as being the source of horsemeat found in burgers there.

CNN: Meat industry under scrutiny as horsemeat scandal spreads

Europe's food retailers depend on a complex network of brokers, cold stores and meat-cutting plants around the continent from which to source the ingredients wherever they are cheapest, says the BBC's Christian Fraser, in Paris.

BBC: Horsemeat found in Ikea meatballs in Czech Republic

"If it's possible to source the raw ingredients for a mobile phone - and I am not talking anything to rival Apple - I'll certainly have a good bash, " he says.

BBC: Can a family survive for a year on British-made goods?

The ingredients list is your best source of information.

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