Comparison Between Modified Atmosphere Packaging & Vacuum Packaging

Both modified-atmosphere and vacuum packaging are methods used to extend the time in which food products, especially meats and other products that can harbor harmful bacteria, can be kept on store shelves and in home refrigerators and still look fresh and be safe to eat.

Modified-Atmosphere Packaging (MAP)

• The U.S. Department of Agriculture's Food Safety and Inspection Service defines modified-atmosphere packaging as a "packaging method in which a combination of gases such as oxygen, carbon dioxide and nitrogen are introduced into the package at the time of closure." Carbon dioxide or nitrogen may help meat preserve a pink, fresh appearance. The package may appear inflated, and when opened, the escaping gases may make an audible "whoosh" sound.

Vacuum Packaging

• The USDA defines vacuum packaging as "rigid or flexible containers from which substantially all air has been removed before sealing." The wrapping of a vacuum package is usually right against the contents and consists of a heavier material than standard store shrink wrappings. Juices may be visible around the meat, but cannot leak until the package is opened.

Freezing

• The USDA endorses freezing vacuum-packed meats as they come from the store. Meats in modified-atmosphere packaging may be more likely to suffer freezer burn or drying because of the larger amount of air in contact with the surface of the meat. Freezer-burned meat is still safe to eat, though it may be tougher and less tasty.