The technical term for cooking food in a vacuum bag is "sous-vide." The idea behind cooking food in a vacuum-sealed bag is to maintain the integrity of the ingredients. To sous-vide food, you put the food in the bag and remove all of the air from the bag so it is airtight. The food is then cooked in a water bath on low heat for an extended period of time.
Place meat in a vacuum bag. You can cook fish, chicken and steak, among other meats, using the sous-vide method.
Add your choice of marinade or seasoning to the vacuum bag. Sit the bag in the freezer and leave it there long enough to freeze just the liquid ingredients. This will ensure they do not become sucked out when you use the vacuum sealer.
Remove all of the air from your bag with your vacuum-sealing device.
Refrigerate your vacuum bag for about 60 minutes. Turn the bag over after 30 minutes to ensure the ingredients are evenly coated in the seasoning or marinade.
Fill a pot with lukewarm water. Use a cooking thermometer to check the temperature of the water. Use the burner of the stove to get the water temperature between 54.4 to 60 degrees Celsius.
Put the vacuum bags with your food in them into the pot of water. Keep a close eye on the temperature of the water with the digital thermometer. Maintain the temperature between 130 to 140 degrees Fahrenheit by increasing or decreasing the temperature of the burner as needed. You can also add ice or cold water if the temperature climbs.
Allow your food to soak in the water for at least 90 minutes. You can leave the food in the bath for up to 12 hours as long as the temperature is steadily maintained.
To brown sous-vide meat, remove it from the bag after cooking. Cook each side of the meat in a frying pan with oil for two minutes.