Research has shown that oxygen and moisture are the primary causes of food spoilage, and that components bind or "oxidize" with oxygen. The most effective way to protect food from oxygen damage is to remove the oxygen and replace it with an inert gas. It's nitrogen gas. This gas is now well known for its snack food packaging applications. The shelf life of snack foods such as potato chips, extruded snack foods, breakfast cereals, nuts and other dried fruits is enhanced by evacuating the air surrounding the food in the package.