Loscoe Chilled Foods is part of an investigation into claims beef sold as British was imported from South America.
Last night, Daniel Ryde, a director of the Derbyshire-based company, confirmed its involvement.
He said: “We are actively working with the FSA to assist in a supply chain investigation and to establish the possibility that South American Corned Beef may have passed through one of our slicing sites in March 2021.
“Whilst the investigation is ongoing we cannot comment further as it may prejudice the integrity of the investigation.
“We understand this is an isolated issue that does not concern food safety.
As well as prisons, hospitals and schools, it supplies supermarkets and government departments.
The investigation by the National Food Crime Unit — part of the FSA — has also seen upmarket supermarket Booths pull products from its shelves.
The NFCU’s Andrew Quinn said it was looking at how the pre-packed meat and deli products made it on to shelves.
He added “This is not a food safety issue but a matter of food fraud.”