The rule change that could have sparked the horsemeat scandal

The scandal has been confined to beef products, so far. Photo: Press Association

One of Britain's most prominent food scientists has told ITV News that recent changes in regulations sparked the horsemeat scandal

Dr Mark Wolfe, worked for 25 years as a Government food Scientist - including The Food Standards Agency. Today he told us that a change in rules "must have contributed to a large extent to this situation".

Dr Wolfe says a shift in policy last year meant a type of burger meat produced in the UK could no longer be used, forcing producers of "value" meals to buy overseas.

The policy change did not only effect beef, but also lamb, so Dr Wolfe also believes those products should also be checked for contamination.

When cuts of meat are removed from a carcass a lot is left on the bone - this used to removed and called "DSM".

It came out as a kind of paste, but the important thing for the food industry was that they could count it as meat when it comes to the label.

However, a rule change last year changed that - meaning it was no longer counted as meat. As a result, the producers of "value" and "budget" products went overseas to find other produce to bulk out their products. Dr Wolf said:

It does suggest that a lot of manufactures who wanted to fill this gap had to go abroad to get their raw materials at the same price

This change, as we now all know, led to the long food chains leading across Europe as manufacturers dealt with international traders selling blocks of frozen meat off-cuts - the replacement for DSM.

When that supply stopped the food manufacturers had to find alternative sources, probably they went abroad and we've seen the longer the food chain becomes the harder it is to know what goes on the documentation and whether it can be verified.