Cooked meats to be used in sandwiches should be cooled quickly after being cooked, and kept refrigerated until the sandwich is made. Use a fork or tongs to place meat, poultry, or fish in the sandwich. This will prevent the spread of bacteria from fingers to food. One way to assure safety of the meat in a sandwich is to make the sandwich and freeze it. The frozen sandwich will thaw in time for lunch and will also keep the rest of the lunch cool until then.
Most sandwiches freeze well if they are frozen in plastic bags designed for freezing.
There will be some loss of quality if the sandwich is frozen in a thin sandwich bag. Sandwich fillings that freeze well include cheddar cheese or cream cheese, sliced or ground meat, sliced or ground poultry, fish, cooked egg yolk, and peanut butter. Fillings that contain raw vegetables such as lettuce, carrots, or tomatoes, and those with egg white, jelly, or mayonnaise do not freeze well. The vegetables become limp, the egg whites become tough, and the other fillings make the sandwich soggy. To prepare frozen sandwiches, spread each piece of bread from edge to edge with softened butter or margarine.