The big supermarkets put relentless pressure on their suppliers to give them the lowest price possible.
The suppliers respond in turn by downgrading the quality of their meat and using cheaper ingredients.
In its classic form, a burger should be nothing more than minced beef, salt and freshly ground pepper. But in the supermarket, even a premium burger has to contain only 80 per cent of the meat named in the title, usually beef or chicken. Burgers are particularly vulnerable to such downgrading because they are made of processed meat, which dramatically widens the scope for adulteration compared to, say, a chicken breast or a piece of steak. Indeed, the process of mincing hides a multitude of sins.
The rest can be made up of assorted additives, fat and soya protein to bulk out the mixture.
When it comes to economy burgers (like those tested from the four major chains by the Irish Food Authority’s horse meat investigation), just 59 per cent of content needs to be meat.
Even this 59 per cent is allowed to include the unsavoury-sounding ‘mechanically recovered meat’ (MRM), which is little more than a pink slurry produced by grinding every last remnant from the animal’s carcass under high pressure.
Although if this substance is added to the cheap and uncheerful mix, it would have to be labelled.
Until recently, MRM was allowed to contain even the spinal column of cows, though this was finally banned after concern that such a source could be passing on BSE to humans. Yet the quality remains poor.