The potato chip packaging bags on the market are mostly composite materials made of biaxially oriented polypropylene film, low density polyethylene and aluminum foil. Among them, biaxially oriented polypropylene film is used as the outer layer material, because of its good printing adaptability, good gloss and moderate price. Aluminum foil is used as the inner material, which can play the role of moisture-proof.
Many potato chip manufacturers will require high barrier properties, high light protection, good oil resistance, and exquisite gravure printing when purchasing packaging materials. The usual structure is: BOPP/VMPET/PE、BOPP/VMPET/CPP、BOPP/VMPET/EX-PE/PE, etc.
Generally, the packaging material used for potato chips products is composite film packaging material, which is a combination of printing layer/aluminized barrier layer/heat sealing layer. It can be seen that the aluminum layer is not in direct contact with the food, and is usually in direct contact with some safer plastics. And food packaging, the products of regular enterprises must be certified for safety before they can be eaten with confidence.
Potato chips contain a lot of oil and are more afraid of oxidation. In order to ensure the shelf life of potato chips, the barrier properties of packaging materials are usually relatively high. Aluminum is a material recognized by the whole world with excellent ductility and barrier properties. Therefore, it is widely used in the field of potato chip packaging.
In addition, when packaging potato chips, it needs to be filled with gas, which is to extend the shelf life and ensure that the food does not deteriorate. There is oxygen in the air, which will make the food oxidatively deteriorate. Nitrogen is a very commonly used protective gas, and it does not react with other substances under normal conditions, so it is very suitable for inflatable packaging. Carbon dioxide also doesn’t oxidize food, and while it’s an acidic gas, it’s not very good, but it’s still a lot better than oxygen for dry food. Because filling gas into bag is a technical process, it needs a professional packaging machine to complete it.
Therefore, under the dual action of barrier packaging material and nitrogen, potato chips can be better protected.