Two leading UK catering firms have announced the withdrawal of frozen beef products after horse DNA was found.
Sodexo, which supplies food to schools, care homes and the Armed Forces, said beef had been pulled from its UK sites with immediate effect.
The firm said despite repeated guarantees from suppliers, its checks had uncovered a frozen beef product that tested positive for equine DNA.
Another firm, Scotland Excel, which works mainly with councils, said it advised customers to stop using stocks of frozen burgers after horse DNA was found in a frozen beefburger at North Lanarkshire Council.
The company, which named Brakes as their supplier, stressed the move was a precaution.
Sodexo said its Tillery Valley Foods business, which supplies meals to the healthcare sector, was not affected.
A spokeswoman would not confirm which of its sites had been supplied with the frozen products. Catering at Ascot Racecourse, which hosts Royal Ascot, attended each year by the Queen, is run by Sodexo Prestige, according to the firms website.
The spokeswoman also declined to name the supplier of the beef products which tested positive for horse DNA and would not say if it was a British or Irish manufacturer.
It comes hours after the owner of Birds Eye recalled ready meals from shelves in four countries.
The brands traditional spaghetti bolognese 340g, shepherds pie 400g and beef lasagne 400g are being withdrawn from sale in the UK and Ireland.
Birds Eye withdrew its beef lasagne from sale in the UK and Ireland
They were made by supplier Frigilunch NV, which also produces a branded chilli con carne sold in Belgium that has tested positive for traces of horsemeat.
Birds Eye said: We want to reassure you from the testing we have completed that all Birds Eye beef burgers, beef pies and beef platters do not contain horse DNA.
Whilst this is not a food safety issue, it is clearly unacceptable. In accordance with our high standards, we are immediately withdrawing this product from sale in Belgium.
Iglo Foods Group, the parent company of Birds Eye, said in addition to the three product recalls in Britain and the same meals in Ireland, it was withdrawing eight products in Belgium and one in the Netherlands.
The Continental food recall also affects ox tongue, mince, meat balls and hamburgers.
In recent weeks it has emerged European meat supply chains had been contaminated with horsemeat, which forced a number of British supermarkets to recall products.
The France-based Findus food company has also been hit by the scandal.
The Birds Eye revelation comes after it initiated a Europe-wide testing programme for horse DNA of its suppliers and on its finished beef products.
Environment Secretary Owen Paterson said: Its unacceptable for any products to be marked as beef, when they also contain horse meat. Thankfully these results show that the vast majority of products on our shelves match whats on the label.
Food businesses from throughout the industry, including retailers, manufacturers, caterers and other wholesalers, are putting enormous effort into getting this testing completed as quickly as possible. Its an important first step from them in rebuilding the certainty and trust that consumers deserve.
The Food Standards Agency (FSA) released the latest tranche of test results submitted by the food industry earlier. They showed that out of 1,133 meat products checked, only six including Sodexos were positive for horse.
Results of industry tests on 2,501 beef products collated by the FSA last week revealed 29 positive results, relating to Aldis special frozen beef lasagne and special frozen spaghetti bolognese, Co-op frozen quarter-pounder burgers, Findus beef lasagne, Rangelands catering burger products, and Tesco Value frozen burgers and Value spaghetti bolognese.
The FSA said no tests to date on samples containing horse DNA have found the veterinary drug phenylbutazone, or bute, to be present.
Retailers have completed about 90% of their tests so far, while manufacturers, caterers and wholesalers have completed about 80% of their tests, according to the FSA. Further test results are due next Friday.
List Of Withdrawn Beef Products
Updated: 12:23pm UK, Friday 22 February 2013
The following products have been removed from supermarket shelves following the horsemeat scandal:
Tesco, Lidl, Waitrose, Sainsburys, Iceland, Asda, Co-Op and Dunnes: Dalepak own-label beefburgers
Aldi: Dalepaks specially selected Aberdeen Angus quarter pounders, Oakhurst beef quarter pounders and frozen Oakhurst beefburgers, Todays Special frozen beef lasagne, Todays Special frozen spaghetti bolognese
Asda: four lines of Freeza Meats frozen burgers, Smart Price economy beefburgers, 500g beef bolognese sauce, 600g beef broth soup, 500g meat feast pasta sauce and 400g chilli con carne soup
Birds Eye: beef lasagne 400g, spaghetti bolognese 340g, shepherds pie 400g.
Findus UK: beef lasagne 320g, 360g, 500g
Tesco: Everyday Value beefburgers and beef quarter pounders, Everyday Value spaghetti bolognese
Waitrose: Essential British frozen meatballs 480g
How Horsemeat Scandal Unfolded
The horsemeat scandal has been unfolding for weeks and products have been flying off the shelves, although not in a good way. Where did it all begin?
January 16: The Food Safety Authority of Ireland says beefburgers with traces of equine DNA, including one product classed as 29% horse, are being supplied to supermarkets by Silvercrest Foods in Ireland and Dalepak Hambleton in Yorkshire, subsidiaries of the ABP Food Group.
Ten million suspect burgers are taken off the shelves, including by retailers Tesco, Lidl, Aldi, Iceland and Dunnes Stores. A third company, Liffey meats, based in Co Cavan, Ireland, was also found to be supplying products to supermarkets with traces of horse DNA.
January 17: The ABP Food Group suspends work at its Silvercrest Foods plant in Co Monaghan, Ireland, until further notice. Sainsburys, Asda and the Co-op later withdrew some frozen products as a precaution but had not been found to be selling contaminated food.
January 23: Burger King, which is supplied burgers by ABP Food Group, switches to another supplier as a precautionary measure.
January 25: Waitrose removes a range of frozen burgers made by Dalepak but says its burgers have been tested and are 100% beef. The Food Standards Agency said tests at a Dalepak plant in North Yorkshire had found no traces of meat contaminated with horse or pork DNA.
However, Aldi found traces of pig and horsemeat in samples taken from three lines of Dalepak burgers. It withdrew Specially Selected Aberdeen Angus Quarter Pounder, Oakhurst Beef Quarter Pounders and Frozen Oakhurst Beefburgers from sale.
February 4: Production at a second meat supplier, Rangeland Foods in Co Monaghan, is suspended after 75% equine DNA is found in raw ingredients, The Department of Agriculture confirm.
February 5: Frozen meat at Freeza Meats company in Newry, Northern Ireland, is found to contain 80% horse meat, The Food Standards Agency Northern Ireland said. It is potentially linked to the Silvercrest factory in the Republic of Ireland. Asda withdraws products supplied by Freeza Meats.
February 6: Tesco and Aldi take down frozen spaghetti and lasagne meals produced by French food supplier Comigel following concerns about its Findus beef lasagne.
The FSA reveals a second case of gross contamination after some Findus UK beef lasagnes were found to contain up to 100% horse meat. The products were made by French food supplier Comigel.
February 8: Aldi withdraws its Todays Special Frozen Beef Lasagne and Todays Special Frozen Spaghetti Bolognese after tests showed the products contained between 30% and 100% horsemeat.
February 12: Peter Boddy slaughterhouse in Todmorden, West Yorkshire, and meat processing plant Farmbox Meats at Llandre in Aberystwyth, West Wales, are raided and shut down, pending investigations.
February 14: New figures released by the Food Standards Agency (FSA) show eight horses slaughtered in the UK between January 30 and February 7 tested positive for the veterinary painkiller bute. Three men are arrested at the raided plants in Aberystwyth and Todmorden, West Yorkshire.
February 19: Swiss food giant Nestle announces a decision to recall beef-based products in Italy and Spain after horse DNA is discovered in products bearing the Buitoni and Bolognaise Gourmandes labels.
February 22: Birds Eye recalls beef lasagne, spaghetti bolognaise and shepherds pie from shelves in Britain and Ireland. Parent company Iglo also pulls chili con carne in the Netherlands and eight products in Belgium.
Caterers Scotland Excel and Sodexo both announce a decision to remove frozen beef products as a precautionary measure. Scotland Excel said equine DNA had been found in frozen beef burgers provided by supplier Brakes.