By Keith Gladdis and Claire Ellicott of MailOnline
Of the 13 samples of burger analyzed, nine tested positive for horse DNA
Shocking: Tests carried out at Silvercrest in Ireland have confirmed that a powder imported from Holland caused the contamination
The Dutch meat supplier believed to be responsible for contaminating British burgers with horse meat was still operating last night despite being under investigation.
New DNA tests on burgers made at the Silvercrest processing plant in Ireland have confirmed that an imported protein powder used as a filler to help bulk out the burgers caused the contamination.
It is understood that the supplier of the powder is based in the Netherlands, where authorities have confirmed an investigation is under way.
The same supplier provided the ingredient – usually made from the unwanted parts of a cattle carcass – to another affected company in Ireland called Liffey Meats and the Dalepak processing plant in North Yorkshire.
The Silvercrest factory which makes burgers for outlets including Tesco, Asda, Sainsbury’s, the Co-op and Burger King has temporarily ceased production after two thirds of burgers tested by officials were found to contain horse meat.
But the Dutch authorities last night said the suspected supplier of the powdered protein filler was still in operation because there was no risk to public health.
The Netherlands Food and Consumer Product Safety Agency also refused to name the processor under investigation until a problem was proven or a product recall notice was issued.
A spokesman said: ‘The Irish food safety authority has been in touch and they will take part in an investigation into what happened. There are one or more companies that will be investigated.’
The Irish agriculture minister Simon Coveney yesterday said his department would soon be able to identify the supplier of the filler used in Tesco beefburgers which contained 29% horse meat.
He said: ‘We are close (to knowing the source). We have our suspicions but what’s required now is proof. When we have full facts then we will be able to draw conclusions and name names.’
Horse steaks used to be popular in the Netherlands but its consumption has grown out of fashion in the last 20 years.
However the country remains a major processor of horse meat imported from abroad, largely south America.
And horse meat has been used to bulk out more expensive meat in Dutch snack products in the past.
In 2007 checks on popular Dutch snacks such as bitterballen, meatballs made from a mix of beef and veal, found horsemeat in almost a third (32%) of those tested.
And in 2008 a Dutch consumer affairs programme found horse was still used by many producers of frikandellen, a deep fried hot dog.
Same supplier: Fast food giant Burger King UK was drawn into the row today as it uses the same supplier as supermarkets where burgers were found to contain horse meat
Initially it was thought a supplier from Spain, where 12,900 tonnes of horse meat were produced last year, could have been another possible source of the outbreak.
But the body which represents beef producers in Spain said they have only supplied cuts of meat to ABP Foods, the company that owns both Silvercrest and Dalepak, and the not powdered beef protein filler blamed for the contamination.
Work was halted at the Silvercrest factory after tests on burgers produced between January 3 and 14.
Of the 13 samples of burger analysed, nine tested positive for horse DNA.
Mr Coveney said the horse meat was found only in very cheap burgers.
He said: ‘When you have a food industry that is driving down costs all the time well then suppliers will look to get the cheapest product.’
Mr Coveney also admitted he ‘did not know’ how long horse meat may have been used in the burgers.
British farming leaders yesterday demanded immediate action by UK supermarkets to improve their sourcing and labelling of food in the wake of the horse meat burger scandal.
The National Farmers Union (NFU) warned that consumer confidence in the UK food industry had been ‘severely undermined’.
NFU president Peter Kendall said the integrity of UK-produced meat was being compromised by the use of cheaper imports which did not meet the same stringent monitoring systems.
He said retailers must take immediate action to address the integrity of their suppliers and ensure that UK products are easily distinguishable and clearly labelled, so customers can make a conscious decision on the food they buy.
Tesco has apologised for selling burgers containing horse meat.
Aldi, Lidl and Iceland have also withdrawn burgers from sale after they were found to contain horse meat.
Sainsbury’s, Asda and the Co-op later withdrew some frozen products but stressed that the move was ‘purely precautionary’ and they had not been found to be selling contaminated food.
Ten million burgers have been taken off supermarket shelves across Ireland and the UK as a result of the scandal.
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