Vacuum Packing Machine Suppliers & Manufacturers

Chamber vs external vacuum sealers and MAP packaging

Vacuum packaging removes air from a flexible bag or pouch containing the product and then seals the bag under vacuum, extending shelf life by reducing the oxygen available for microbial growth and oxidative spoilage. Chamber vacuum sealers: the entire product and bag are placed inside a sealed chamber; the machine evacuates the chamber (and therefore the bag) to the target vacuum level; the bag is then sealed by a heat-seal bar inside the chamber; the chamber is then vented to atmospheric pressure, which collapses the bag tightly around the product; the sealed pack is removed. Chamber vacuum sealers are suitable for liquids, sauces, marinades, soups, and wet products — because the vacuum is applied uniformly to the entire chamber, liquids do not boil or spray as they would in an external vacuum sealer. They are also the standard for solid food products (meat portions, cheese, fish fillets, ready meals, deli meats), hardware components, and medical device packaging. External vacuum sealers (nozzle vacuum sealers): the bag is placed outside the machine and a nozzle is inserted into the open end of the bag; the machine evacuates through the nozzle and then retracts and seals the bag. Suitable only for dry, non-liquid products; simpler and lower cost but less effective than chamber vacuum. Thermoforming vacuum packaging: a thermoforming machine forms a rigid or semi-rigid tray from a bottom web, the product is placed in the formed cavity, and a top film is applied and sealed under vacuum or MAP gas. The result is a skin pack or tray format — the standard for retail fresh meat, cheese, and seafood. Modified Atmosphere Packaging (MAP): instead of or in addition to vacuum, a gas mixture (typically CO₂ and N₂, sometimes with added O₂ for fresh red meat) is flushed into the pack before sealing. MAP extends shelf life of fresh products while maintaining colour and freshness — the standard for retail meat, poultry, seafood, and bakery. Gas-flush machines include a gas dosing system integrated with the vacuum and sealing cycle.