Aseptic packaging is widely used all over the world for long-term storage of liquid food products: milk, juices, soups. The essence of the method, developed in the 60s of the 20th century, consists in separate processes of sterilization of the product (as a rule, the method of heating to a temperature of 140-1500 C for a few seconds is used), packaging and their subsequent connection under sterile conditions. Such an effect kills pathogenic microorganisms, and also makes it possible to exclude re-infection from contact with the external environment, which prolongs the shelf life of food products. For example, milk poured into aseptic packaging can be stored for 6 months if the temperature is maintained.
Characteristics of aseptic packaging
In addition to the requirements for sterilization, aseptic packaging must meet a number of characteristics that are important for the long-term storage of products:
- low permeability of gas, in particular oxygen. This property allows you to reduce the likelihood of food contact with the environment, allowing you to preserve the original taste, aroma and color;
- physical and mechanical strength. Associated with different transportation conditions;
- resistance to temperatures, gases, radiation. Most often, chemical action with hydrogen peroxide, treatment with saturated steam, hot air or extrusive heat, ultrasonic action, irradiation are used for sterilization;
- inertia. Components of aseptic packaging should have a low migration rate into food.
To achieve all of the above properties, aseptic packaging contains more than one material in its structure, which are combined by means of lamination or coextrusion methods.
There are several main types of such packaging:
- cardboard boxes made of polymeric materials. The packaging itself is cardboard laminated with polymers produced from renewable sources;
- foil packaging. Similar to the first type, but aluminum and polyethylene are applied to the cardboard from the inside, creating an additional barrier between the product and the external environment;
- plastic film bags with sealed plastic necks, placed in a cardboard box. Most often, this type is used for packaging dairy products.
Aseptic packaging has a number of advantages, including:
- Environmental friendliness. Manufacturers use recyclable materials, most often cardboard, the rest are polymers that are recyclable.
- No preservatives. Unlike other methods to preserve the properties of products, the aseptic method is based on sterilization, and not on the addition of preservatives and other substances that are unsafe for humans.
- Economic benefit. The total weight of the filled package accounts for 97% of the product and only 3% of the packaging material.