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Microwave puffing section

The PEX technology is a quasi-continuous "refinement process" patented in several countries, in which pre-dried fruits and/or vegetables (so-called SD products > semi dried) are preserved by dehydration to below 2% water content.
The SD products are always delivered in cleaned and calibrated condition, cut into cubes, strips, slices, etc. There is therefore practically no waste on site.

The SD products are placed in trays (bowls with 800mm Ø) in a geometrically specially designed vessel, which is equipped with microwave transmitters. After a short temperature-controlled heating of the product by microwaves, the vessel is evacuated abruptly. Under vacuum and further exposure to microwaves a "puffing" of the product takes place (PEX > Product EXpanding). During this treatment step, the cell structure of the product is simultaneously changed by disintegration, whereby high-quality product properties (such as significantly higher taste intensity!) are achieved without damaging the product. At the usual working pressure of approx. 20 mbar in the PEX process, the water contained in the product boils and evaporates already at approx. + 17°C.

Infrared drying and cooling system

In a further process step, the trays are transferred to a fully automatic infrared post-drying unit for final drying of the products - while maintaining or lowering the vacuum - and brought to any desired residual moisture content. Before the final product is removed, the trays are temporarily stored on cooled heat exchanger plates to ensure that the final products retain their shape. After the trays have been removed from the vacuum, the final packaging is done in aluminium laminated foil bags under nitrogen. Thus the high quality of the end products is maintained for a long time. The PEX process has already been in use for approx. 10 years and there is very good operating experience.

In the meantime, the quasi-continuous PEX technology has been further developed and supplemented, so that today a fully automatic, continuous ("fifo" = first in - first out) PEX(C) technology can be offered.

If it is desired to start with "freshly harvested" raw material (e.g. when setting up the plant at the place of cultivation), suitable washing, peeling, cutting and drying plants should be installed upstream of the PEX process.

A renowned international plant manufacturer is available for the realisation and construction of the plants, if required.

Over 10 years proven technology to produce healthy and crispy snacks from fruits and vegetables!