The supermarket giant said a number of products labelled as “Just Cook Chicken Breasts with Piri Piri sauce” actually contained chicken and bacon lattice instead – which includes milk and wheat in the ingredients.
The pork, milk and wheat were not mentioned on the label.
The food could be fatal for those with wheat or milk allergies, and could offend people who do not eat pig meat because of their faith.
A Sainsbury’s spokesman said: “It has been brought to our attention a small number of packs labelled Chicken Breasts with Piri Piri Sauce contain chicken and bacon lattice which has cheese, wheat and pork that are not declared on the label.
“As a precautionary measure, we are asking customers who have purchased this product to return it to their nearest Sainsbury’s store, where they will receive a full refund.
“No other products or date codes are affected by this issue, and we apologise for the inconvenience this may cause.”
The Food Standards Agency (FSA) issued an ‘allergy alert’ over the packs – which come in a 326g size with a ‘use by’ date of 24 January 2016.
It warned: “The product is a possible health risk for anyone with an allergy or intolerance to milk or milk constituents and/or an allergy to wheat or intolerance to gluten.”