"Unfortunately, the testing method we use detects just the quality ... the presence or non-presence of horse DNA," said Jan Vana, a senior official at the State Veterinary Administration. "At the moment, we can't say the quantity of it."
Spanish authorities, meanwhile, announced that traces of horse meat were found in a beef cannelloni product by one of the brands of Nestle, a Switzerland-based food giant.
In a statement on its website, Nestle Spain said it was withdrawing six "La Cocinera" products and one "Buitoni" product from store shelves. It said it was taking the action after traces of horse meat were found in beef bought from a supplier in Spain and that it was taking legal action against the company.
Processed food products — a business segment with traditionally low margins that often leads producers to hunt for the cheapest suppliers — often contain ingredients from multiple suppliers in different countries, who themselves at times subcontract production to others, making it hard to monitor every link in the production chain.
Standardized DNA checks with meat suppliers or more stringent labeling rules on disclosing the origin of processed food's ingredients will add costs that producers will most likely hand over to consumers, making food more expensive.
The scandal has created a split in the European Union between nations like Britain, which see further rules as a protectionist hindrance of free trade under the 27-nation bloc's single market, and those calling for tougher regulation, including Austria and Germany.
"Consumers have every right to the greatest-possible transparency," German Agriculture Minister Ilse Aigner said.
At the meeting in Brussels, several EU agriculture ministers called upon the Commission, the bloc's executive arm, to speed up presenting a proposal on tougher regulation by this summer.
The scandal began in Ireland in mid-January when the country announced the results of its first-ever DNA tests on beef products. It tested frozen beef burgers taken from store shelves and found that more than a third of brands at five supermarkets contained at least a trace of horse. The sample of one brand sold by the British supermarket kingpin Tesco had more than 25 percent horse meat.
Associated Press writers Juergen Baetz in Brussels, Karel Janicek in Prague and Ciaran Giles in Madrid contributed to this report.
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