BRITAIN: Food processors have been caught on video boasting that they have developed undetectable methods of adulterating the chicken which goes into UK hospitals, schools and restaurants with cheap beef waste and water.
Tests by a television programme have also shown samples of British supermarket Sainsbury's Blue Parrot chicken nuggets to contain both bovine and pork DNA.
The company says the bovine DNA comes from milk protein, and the presence of pork DNA in one sample may be the result of contamination in the laboratory.
Secret filming for BBC's Panorama has revealed that vast quantities of frozen chicken coming into the UK each week have been injected with beef proteins.
BBC reporters were told by Dutch manufacturers that beef DNA can now be manipulated in such a way that the safety authorities' tests cannot detect it.
Adulterated chicken has been imported widely by British wholesalers. Brakes, a leading supplier to schools, hospitals and restaurants, has unwittingly imported chicken with beef DNA, according to laboratory tests for the BBC.
On Panorama tomorrow, a German protein supplier for huge Dutch chicken companies tells undercover reporters his firm, Prowico, has developed secret methods to break down the DNA of the proteins so that no government tests can detect the beef.
Tests have found that some chicken fillets are as much as 50 per cent added water.
The director of Prowico, Mr Theo Hietbrink, says that his beef proteins are guaranteed to be "PCR-negative" - polymerase chain reaction (PCR) is the test authorities use to find DNA from different species.
The owner of Surplus, the Dutch company which blends the Prowico proteins into powder, tells the undercover reporters the industry has been extracting hydrolysed beef proteins to inject into chicken and other meats for more than 10 years.
Panorama sent 12 samples of Dutch chicken to the laboratory used by British authorities but it did not find any beef DNA. Several of the same samples were then sent to a private Irish lab, which, using more sensitive techniques, detected beef DNA in several samples.
Brakes said it had conducted its own independent PCR tests on chicken it imported but they were negative.
The Sainsbury's Blue Parrot chicken nuggets are made from chicken from the UK, Germany and Holland. The company said its own independent tests had found no pork DNA in its nuggets and the presence of beef DNA was most likely to be caused by milk, a labelled ingredient.
Prowico and Surplus both say that they have never sold proteins or additives without declaring their contents.
Prowico says its PCR-negative proteins are made to be very pure, and Surplus said it has never intended to mislead.