New Gospel of Aseptic Food Packaging Technology Packaging Market

[China Packaging Network] Aseptic packaging technology emerged in the late 1940s and gained significant traction since the 1960s with the development of plastic packaging materials. This innovation has opened up a vast market for aseptic packaging, offering benefits such as minimal nutrient and flavor loss, lower costs, ease of storage and transportation, and an attractive appearance. As technology advances, the equipment and materials used in aseptic packaging have become more sophisticated, leading to a growing market. In developed countries, aseptic packaging accounts for over 65% of liquid food packaging, highlighting its promising future.

What is Aseptic Food Packaging?

Aseptic food packaging involves sterilizing both the food (such as beverages, dairy products, and seasonings) and the packaging environment before sealing it in a sterile container. This process allows the product to have a long shelf life without refrigeration or preservatives. In simpler terms, aseptic packaging ensures that the packaging material, container, and contents are all sterilized before being sealed in a sterile environment. The term "aseptic" in the food industry refers to a condition where the number of non-pathogenic bacteria per gram of food is less than 10. If these bacteria do not multiply, the food remains safe for consumption even when stored at room temperature.

Sterilization Methods for Packaging Materials

Aseptic packaging includes sterilizing the packaging materials, the contents, and the environment. Common methods include chemical sterilization using hydrogen peroxide and ultraviolet (UV) light. These techniques ensure the safety and longevity of packaged products.

1. Chemical Sterilization – Hydrogen Peroxide

Hydrogen peroxide is one of the most widely used disinfectants in aseptic packaging. It is effective when used at concentrations between 25% and 30%, and at temperatures around 60-65°C. When heated, hydrogen peroxide evaporates from the surface of the material, enhancing its bactericidal effect. The sterilization process typically involves immersing or spraying the packaging containers with hydrogen peroxide, followed by heat treatment to remove any residue, leaving behind only water vapor and oxygen.

2. UV Sterilization

UV sterilization is most effective at wavelengths between 250-360 nm. It works by disrupting the DNA of microorganisms, preventing their reproduction. While UV sterilization is safe, cost-effective, and leaves no residue, it is less effective compared to chemical methods. Therefore, it is often used in combination with other sterilization techniques to ensure maximum effectiveness.

Common Aseptic Packaging Formats

There are several common forms of aseptic packaging, including aseptic cardboard, sterile cups, aluminum/plastic bags, and plastic bottles. Each type is designed for specific applications and offers unique advantages.

1. Aseptic Cardboard Packaging

This type of packaging uses a composite material made of cardboard, aluminum foil, and polyethylene. The cardboard provides structural support, while the aluminum foil acts as a moisture and oxygen barrier. Polyethylene is used as the inner layer for heat sealing. Aseptic cardboard packaging is commonly used for dairy products, juices, and beverages, with capacities ranging from 200 to 1000 ml.

2. Sterile Cup Packaging

Sterile cup packaging uses multilayer co-extruded sheets, such as NAS sheets, which feature a peelable outer layer. These sheets are designed to maintain sterility during the packaging process. They also incorporate high-barrier materials like PVDC or EVOH to extend shelf life. This type of packaging is ideal for products requiring long-term preservation without refrigeration.

3. Aseptic Bag Packaging

Aseptic bag packaging is suitable for larger volumes, ranging from 5 to 1000 liters. It is often used for thick stock or base materials and can be directly sold to consumers. This format has largely replaced traditional metal or plastic buckets and eliminates the need for preservatives.

4. Aseptic Aluminum/Plastic and Plastic Bottle Packaging

These packaging formats use aluminum or plastic composites, often involving dry or cast lamination. Plastic bottles, especially those made from PP or PE, can be sterilized during molding and filled immediately. This ensures a sterile environment throughout the entire packaging process.

5. Aseptic Composite Paper for Liquid Foods

Aseptic paper packaging, particularly aluminum foil composites, is becoming increasingly popular due to its ability to maintain product quality for over 12 months at room temperature. Key technical considerations include proper surface treatment of the base paper, controlling the thickness of the PE layer, and ensuring the innermost layer meets safety standards. These factors contribute to the overall effectiveness and efficiency of the packaging system.