Aseptic steam blowing without chemical agents

Aseptic solutions for high microbiological sensitivity.

Liquid foods or beverages that require sterilized or aseptic containers are those that are sensitive or highly sensitive to microbiological contamination and must maintain sterility or hygienic quality for long periods without refrigeration.

Suitable products include:

Sensitive products: fruit juices, isotonic drinks, etc.
Highly sensitive products: UHT milk (Ultra High Temperature), plant-based milk (soy, almond, oat, etc.), yogurt, probiotics, soups, ready-to-drink tea and coffee.

Production of sterile sealed bottles using Techne aseptic blow-molding system

Why aseptic conditions are important in blow molding.

Aseptic Extrusion Blow Molding of plastic containers means the complete absence of bacteria and contaminating elements. In the dairy sector, this is essential to guarantee safety, preservation, and quality, especially for sensitive non-refrigerated products.

Techne Packaging’s aseptic blow molding machines make it possible to obtain sterile containers without the use of chemical substances, preserving the organoleptic properties of food products.

Download Datasheet

Aseptic technology preserves:

Color

Maintains the original color, a sign of freshness and consistent quality.

Texture

Preserves the correct structure, without alteration or degradation.

Taste

Retains the original aroma, ensuring authentic flavor over time.

Quality

Protects organoleptic and nutritional properties without compromise.

Sealed aseptic bottles: 3 key advantages

Zero contamination

Complete elimination of chemical residues and maximum safety for the end consumer.

Energy efficiency

Steam is used only during sterilization, reducing energy and operating costs.

Optimized storage

Closed-neck bottles are stronger and easier to store.

Standard sterilization vs. Techne

For sensitive products, plastic bottles are often produced using standard Extrusion Blow Molding: they enter a clean room with an open neck, are sterilized internally and externally with chemical agents, then rinsed, dried, and capped in a sterile environment. However, the risk of chemical residues in contact with the beverage remains—critical for products such as milk.

To eliminate this risk, since 1992 Techne has developed an aseptic blow molding system integrated directly into the blow molding machine, using only steam to sterilize air and piping. The result is a closed-neck, sealed, sterile bottle with zero risk of contamination.

Download Datasheet

Stages of the Aseptic Blow Molding process

Aseptic bottles from monolayer to COEX-6

Monolayer aseptic bottles.

For pasteurized and ESL products stored under refrigeration, bottles can be made of a single HDPE layer (neutral or colored), providing a shelf life of 8 to 30 days.

Download Datasheet

COEX-3 aseptic bottles.

To reduce plastic consumption, material recovered from bottle production scraps can be reprocessed and used as an internal layer between virgin plastic layers. This also helps protect the product from light.

Download Datasheet

COEX-6 aseptic bottles.

For dairy products with added vitamins (UHT) stored at room temperature, it is necessary to add adhesive and EVOH barrier layers to protect against light and heat, ensuring long shelf life.

Download Datasheet

Watch the Aseptic process

Frequently Asked Questions (FAQ)

What does “aseptic” mean?

The term “aseptic” refers to a condition free from pathogens or bacterial contamination. In the food industry, it means that the container is internally sterile and ready to hold food without compromising safety.

How many aseptic machines has Techne built?

In 1992, Techne introduced its first machine with sterile blow molding for long-life dairy products, with the major advantage of eliminating the need to rinse bottles with chemical agents before filling. Combined with a co-extrusion head, this solution has since been adopted by many companies in the sector, with over 50 machines installed worldwide for this specific application.

Why can chemical sterilization compromise aseptic containers?

In most lines, bottles are produced with an open neck and then chemically sterilized using peroxide or peracetic acid. Although common, this method poses a real risk of chemical residues, especially in bottles with complex shapes or handles, which come into direct contact with food products.

The greatest risk concerns highly sensitive and basic products that require a 100% aseptic environment, such as:

UHT milk
Plant-based milk (soy, almond, oat)
Yogurt, soups, ready-to-drink tea and coffee

What determines the shelf life of preservative-free liquid foods?

Shelf life depends on several factors:

The pre-treatment process (pasteurization, sterilization, UHT, etc.);
The container (plastic bottles, glass, metal cans, etc.);
The filling method (clean fill, hot fill, ultra-clean, aseptic);
Post-filling and capping processes, if any (autoclave sterilization);
Storage conditions (ambient, cold chain).
The microbiological sensitivity of the liquid food determines the type of packaging line and the resulting shelf life.

Which containers are typically used for highly sensitive products?

For highly sensitive products such as UHT milk, plant-based milk (soy, almond, oat, etc.), yogurt, probiotics, soups, and ready-to-drink tea and coffee, the most commonly used packaging solutions over the past 30 years have been COEX-3 bottles or, in specific cases, COEX-6.

This is because basic products sensitive to visible light (>380 nm) require a protective black barrier in the central regrind layer.
To ensure perfect preservation of organoleptic properties, bottles must be multilayer with a black barrier in the central layer, blown with sterile air and with a sealed dome. Consequently, the filling machine is also of the “Closed-Neck Aseptic” type and chemically sterilizes only the outside of the bottle to avoid altering product quality.

Aseptic Blow Molding.

The safest technology for aseptic and sterile containers.

Contact us