Clear quality assurances are needed before Northern Ireland's health service considers returning to a supplier of burgers which contained horse meat, the region's health minister said.
Contaminated produce from Rangeland Foods in the Irish Republic was sent to hospitals north of the border, Edwin Poots added.
The range was withdrawn immediately once the problem was discovered.
Mr Poots demanded firm guarantees. He said: "We have discontinued using Rangeland burgers. I don't think we will be going back to Rangeland unless they can clearly demonstrate that they have full and proper access to the chain that has delivered meat to them and they can ensure that there is no possibility of other products entering (the chain)."
The health and social care service in Northern Ireland, which includes hospitals and daycentres, spends around £2 million on fresh meat and about £100,000 a year on burgers. Rangeland is one of seven suppliers of frozen foods. The minister said: "We are buying beefburgers, not those containing 30% horse meat. If that is the product we are getting then we need to be satisfied that what we are getting is what we ordered."
Horse meat is much cheaper than beef, retailing for around £700 a tonne compared to £3,000 a tonne, and Mr Poots said somebody was saving money somewhere.
A Food Safety Authority of Ireland (FSAI) statement said: "The FSAI has been informed by Rangeland Foods that it is withdrawing some batches of frozen burger products from customers which contained beef supplied from Poland and have been found to contain equine DNA between 5% and 30% relative to bovine DNA. These burgers have been supplied to the catering and wholesale sectors and are therefore not on sale directly to the consumer."
A Rangeland spokeswoman said the affected meat from the EU was processed in September. Following consultation with the Department of Agriculture, the firm recommenced production at its Co Monaghan plant this month, on the basis that it was using only Irish raw materials.
Northern Ireland's agriculture minister Michelle O'Neill called a special meeting on the horse meat scandal. "I want to show leadership on this issue because it is so important we address the issue of public confidence. The other ministers who did not turn up will have to account for themselves," she said.
A number of other executive ministers were invited to attend the briefing. Those who did attend received an urgent update from senior officials of the Foods Standards Agency (FSA) in Northern Ireland.