Beer bags usually adopt multi-layer composite materials to meet various needs of beer packaging in aspects such as preservation, transportation, and display. The materials of the inner layer, middle layer, and outer layer are usually as follows.
Inner Layer Material:
Generally, food-grade polyethylene (PE) or polypropylene (PP) is selected. These materials have good chemical stability, are non-toxic and odorless, and will not have an adverse impact on the taste and quality of the beer, meeting the safety standards for food contact. At the same time, they have good flexibility and low-temperature resistance, and can adapt to the filling and storage conditions of beer.
Middle Layer Material:
Materials such as aluminum foil or ethylene-vinyl alcohol copolymer (EVOH) are often used as the middle barrier layer materials. Aluminum foil has excellent barrier properties and can effectively block oxygen, water vapor, and light, preventing the beer from being oxidized, getting damp, and deteriorating, and extending the shelf life of the beer. EVOH also has excellent gas barrier properties, which can prevent oxygen from entering the bag and maintain the freshness and flavor of the beer.
Outer Layer Material:
Polyester (PET) or nylon (NY) is usually used. PET has high strength, hardness, and transparency, which can give the beer bag good stiffness and an excellent appearance for display. At the same time, it has good wear resistance and tear resistance, protecting the beer bag from damage during transportation and storage. Nylon has excellent toughness and puncture resistance, which can enhance the durability of the beer bag and is not easy to break even in harsh environments. In addition, the outer layer material is also convenient for printing exquisite patterns and texts for product promotion and brand building.