On Thursday, the Agriculture Minister confirmed the products - supplied to the Loughry and Greenmount campuses by Eurest - tested positive for equine DNA.
The company, which is a subsidiary of Compass, withdrew the burgers from the menu after products from a manufacturer within its supply chain were sent for testing.
"I can confirm that burgers containing horse meat have been supplied to the Eurest outlets at Greenmount and Loughry campuses of CAFRE," the Minister said.
Last week, it was revealed that traces of equine DNA were found in the horsemeat supplied by Compass. The next day, students and staff at the college campuses were told about the contamination.
Its contract with all three of campuses of the College for Agriculture, Food and Rural Enterprise began in August 2011.
Michelle O'Neill confirmed the presence of horsemeat in burgers in response to a written question by the UUP Agriculture spokesperson, Jo-Anne Dobson.
Mrs Dobson also asked if contaminated meat had been found in any buildings where Department of Agriculture staff work.
"I can also confirm Serco provides the catering services in Dundonald House. They are not aware of any instance where horsemeat has been confirmed in any of the products sold by them," the Minister said.
Mrs Dobson, an MLA for Upper Bann, said the Agriculture Minister needs to return consumer confidence to the meat industry.
"The irony is that students at CAFRE colleges spend their school day learning about best farming practice, but when they sit down in the canteen, burgers containing horsemeat are on the menu.`
"Northern Ireland has the best beef in Europe and yet we have a Department of Agriculture procuring meat products from processors who are damaging the stellar reputation of our farmers. Farmers must not become the fall guys for dubious processing practices," she added.
The burgers at Loughry and Greenmount are the latest in a series of products found to contain horse DNA.
Asda has withdrawn two products from sale - an own-brand bolognese sauce and Northern Ireland company Freeza Meats' frozen beefburgers.
The Newry firm said it had been storing meat, which was from Poland, in its cold store as a goodwill gesture after refusing to buy it from trader McAdam Foods, based in the Republic, and that the meat never entered the local food chain.
Earlier this month, it was revealed that Findus beef lasagnes contained up to 100% horsemeat.
Polish authorities have denied their meat suppliers are the source of the contamination.