What is the main principle of vacuum packaging bags?

What is the main principle of vacuum packaging bags? Vacuum bags, also known as decompression packaging, is based on the principle of atmospheric pressure, the main role of the vacuum bag is to remove oxygen, in order to help prevent food mold and deterioration. Vacuum packaging is the bag and food cells within the oxygen pumped off, so that microorganisms lose the “living environment” process. Vacuum bag can also prevent food oxidation, so that the food does not taste, spoilage to reduce the loss of vitamins A and C.
Vacuum packaging materials commonly used double-layer composite film or three-layer aluminum thin composite film made of three sealing bags. Vacuum packaging machine commonly used cavity and external pumping two types of models. China's vacuum packaging technology was developed in the early eighties, and vacuum inflatable packaging technology began to use in the early nineties.

　　Vacuum inflatable packaging is in the extraction of vacuum, and then filled with nitrogen, carbon dioxide and other gases. Nitrogen is an inert gas, filling role, so that the vacuum bag to maintain positive pressure to prevent the bag outside the air into the bag, the food to play a protective role. Carbon dioxide has the active role of inhibiting mold, spoilage bacteria and other microorganisms.

　　Some, such as crunchy and fragile food, easy to deform away from the oil food, sharp edges or high hardness will puncture the vacuum bag and other food, after the vacuum inflatable packaging, vacuum bag inflatable pressure is greater than the bag outside the atmospheric pressure, can effectively prevent the food pressurized by the crushing, deformation, and does not affect the appearance of the bag and printing and decorating. With the promotion of vacuum bag small packages and the development of supermarkets, its scope of application will be more and more extensive, some will gradually replace the rigid packaging.

      Vacuum deoxygenation in addition to inhibit the growth and reproduction of microorganisms, another important function is to prevent food oxidation, because oil and grease foods contain a large number of unsaturated fatty acids, oxidized by the action of oxygen, so that the food tastes bad, spoilage. In addition, oxidation also makes the loss of vitamin A and vitamin C. The unstable substances in the food pigment are affected by the action of oxygen, which darkens the color. Therefore, deoxidation can effectively prevent food deterioration, maintain its color, aroma, taste and nutritional value.