The FoodSaver system vacuum seals foods for extended freezer or refrigerator storage by extracting air and moisture. Without them, your foods last longer and are protected from freezer burn. FoodSaver's primary use is to store leftovers because you cannot cook raw foods in the bags. Reheating is easy using a microwave or stove.
Microwaving
Cut off one corner of the FoodSaver bag with a pair of sharp scissors to allow steam to escape while reheating.
Open the microwave and set the FoodSaver bag on the microwave plate.
Choose a heating option based on the food you are reheating. Times vary widely based on the particular food, how much food is in the bag and how frozen the food is. Start with two to three minutes. Check the food to determine if it's heated thoroughly and return it to microwave for a few more minutes if you feel any cold spots.
Simmering
Fill with water a pot big enough to fit the FoodSaver bag.
Place the pot on your stove top. Turn the burner on to heat the water (covering the pot will do this faster). Adjust the burner as necessary to achieve a simmer. The water should not boil.
Place the FoodSaver bag in the pot of simmering water.
Remove the bag from the pot after about 15 minutes to check for cold spots. Cooking times vary widely based on the food so watch the bag closely. It's done when the food is cooked through completely.