Aseptically filled bag-in-box system

Soft bag liquid packaging technology has a long history. It was not as recent as we thought. Now, we require that packaging products remain in their original state from the time the manufacturer first reaches the end user. Compared with other more traditional liquid packaging methods, the development of soft bag packaging technology has been very smooth. As a result of this packaging technology revolution, the "bag-in-box system" has emerged.

Looking back over the past few years, it is not difficult for us to see that bag-in-box packaging is gradually replacing glass or metal packaging for juices, concentrates or slurries, and this packaging system can be used for both storage and direct consumption.

The packaging system may be a plastic flexible bag placed in a corrugated cardboard box, or a plastic bag placed in a metal container (such as a 55-gallon drum). In most cases, packaging bags for cardboard packaging are usually equipped with filling necks and extraction devices, while packaging bags for drums are only equipped with filling plugs.

Here we distinguish between two different applications:
* In-box bag packaging for finished products;
* Used in bag-in-box packaging for further processing.

Currently, bag-in-box packaging is commonly used to package wine, fresh milk, concentrates, and fruit juices.
From an economic point of view, the application of bag-in-box packaging in the fruit and vegetable industry is similar to that of the wine-making and dairy industry. The advantages of bag-in-box packaging will soon become familiar with people, such as:

* Low production cost of packaging bags;
* Light weight;
* Release and extraction system diversification;
* Use tray capacity as much as possible.

If aseptic packaging is used, in addition to the above advantages, it also has the following advantages:
* Improve the quality of hot cooked foods, especially large-capacity packaging;
* It can be used for completely and thoroughly aseptically extracting packaged goods, and also suitable for partial extraction;
* There is no need for other follow-up cleaning measures like traditional packaging.

In aseptic filling, multilayer films are used. The most common composite foils currently consist of a PE foil and an outer layer of metalized polyester.

The oxygen permeability of this composite foil structure is close to 1 cm 3 /m 2 /24 hours. The latest developments in composite foils originate from a variety of metal foils, and their oxygen permeability is less than 0.01 cm 3 /m 2 /24 hours.

Transparent foil has attracted widespread market attention, its oxygen permeability and the same metal foil. With this composite foil co-extrusion method, up to seven layers of composite foil structures can be obtained.

Bag test

The bag enters the aseptic filling process under aseptic conditions. The bags are sterilized by gamma rays. The irradiation dose is between 10 and 28 kilorays. The bag is exposed when it is in the outer carton. These containers are opened only when they reach the front of the filling device. The bags are then taken out in a closed state.

The principles of aseptic filling and non-aseptic filling machines are basically the same, except that the filling machines used for non-sterile applications are equipped with inductive measuring devices without exception.

Filling process

The filling process is as follows: Manually insert the bag into the fixture. When the "Start" button is pressed, the bag is locked in the filling position. The lid removal device removes the sealing plug from the filling opening of the packaging bag, then rotates sideways, and the filling valve is fixed at the filling opening of the packaging bag. The negative pressure valve located on the filling head opens automatically and evacuates the bag. After the bag has been evacuated, the filling valve opens automatically until it receives a “filling stop” signal from the filling metering device and stops filling.

After filling is completed, the nitrogen valve opens automatically, filling the remaining space in the bag with nitrogen. After filling with nitrogen, the filling valve is raised and rotated to its original position. Pull the plug down and pull the seal cap inside or above the filling port. The stopper slider for alignment of the packaging bag is automatically opened, and the filled packaging bag can be automatically released.

The above sterilizing process is performed in a sterile room. The sterile room is round and has a small area.

The sterile chamber also includes a tubular nozzle that periodically sprays the disinfectant and steam to the inner surface of the cylinder and the insert member during production. The nozzle on the base plate ejects toward its base when the valve is in its home position. The above nozzle can also be used to clean the sterile room. During the production process, the sterile room has been in a state of steam ejection and can maintain a constant temperature.

If the temperature drops, an interference signal will be immediately activated by the all-round warning light. Through the PLC program, it is possible to automatically clean and disinfect the studio and product conduits.

The studio and all embedded elements and catheters can be sterilized with saturated steam of approximately 2 bar within 30 minutes.

In recent years, the efficiency of this filling system has been verified in many fruit juice filling companies. Similar filling machines have been used in the filling of ultra-high temperature sterilized milk, which has been able to maintain good quality even after several months.

This packaging system can be used in a variety of products, four of which are listed below:
* 220 liters / box of concentrated tomatoes. The 220 l/box aseptic filling equipment has been put into use in Italy.

Other products based on tomatoes can also be packaged in this system, again without any problems. The packaging system is professionally designed for storage and cross-border transport. It is also suitable for direct deep processing.

* Fruit concentrates. Whether the nature of the packaged product is a concentrate, a slurry, or a juice concentrate, sterile packaging can provide solutions for its packaging, storage, or transportation.

* fruit juice. For juice, the bag-in-box system is mainly used for large-scale packaging (10 liters, 20 liters or 30 liters).

* Concentrated beverages. This application is evolving so that end users can mix various beverages.

In the next few years, the bag-in-box system will also achieve further significant development and open up new market space. Using the bag-in-box system can reduce the amount of materials used, simplify the cleaning process, enhance the adaptability of transportation, and thus reduce production costs. Bag-in-box packaging can adapt to various requirements and facilitate recycling, thus making a significant contribution to environmental protection.