'Pioneering' system integrates high pressure processing into automated packaging lines

Multivac said a 'pioneering' system that integrates the high pressure treatment of food into a fully automatic packaging line provides the first viable option for the combination of both technologies.

The German-based company said its newly developed “concept”, for which patents have already been filed, could process both vacuum and modified atmosphere packed (MAP) products.

Previously, it was necessary to carry out the high pressure processing (HPP) of food in a separate, manually-loaded system after the product had passed through packaging lines, said Multivac. But the company said it had now managed to integrate the processes - which both boosts line speeds and efficiency.

Multivac said the trends towards increasing requirements by regulatory authorities for the exclusion of harmful microorganisms from foods combined with consumer demand for food with a “natural” taste had been major drivers behind developing the technology.

Throughput maximised

The equipment, developed with Uhde High Pressure Technologie, contains a high pressure unit – consisting of one or more autoclaves – as well as an automatic process that enables treated products to be integrated into a packaging line.

Under a patent pending process, the finished food packs are automatically loaded into transport containers before being subject to HPP in the autoclave. Following this, they are automatically unloaded dried, printed or labelled if required, and finally packed into cartons, said the company.

"In this way, it is for the first time that we can process large, industrial scale production quantities fully automatically in a quasi continuous operation", said Tobias Richter, Multivac HPP product manager.

He added that using the space in the autoclave as efficiently as possible was key to maximising throughput.

"Since the high pressure equipment is round for reasons of optimising the distribution of pressure forces, the loading pattern also has to be designed accordingly", said Richter.

With a favourable pack shape it is possible to handle two to four tonnes of packed food per hour in the high pressure equipment, said the company, adding it can provide support in helping customers choosing the best pack shape and materials for the process. This includes the construction of the necessary test facilities.

HPP for MAP packs

The company claimed it is the world’s first manufacturer to master the process for use with high pressure stable MAP packs. The high pressures in the autoclave are controlled thanks to an innovative process.

"With the help of so-called 'holding torque' we create short rest periods in which the polymer can regenerate. In this way the packaging material is stressed considerably less and retains its functionality even after the high pressure treatment", said Richter.