The firm, John Tudor and Son, of Bridgend, supplies cooked meat to schools and council institutions.
The Food Standards Agency Wales says the firm has withdrawn all its products.
The number of E.coli cases among schoolchildren in three council areas has grown to 56.
The food standards agency says it was possible contaminated products may still be on the shelves of some stores because it believed John Tudor and Son also supplied outlets that sold direct to consumers.


