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Extraction essential for optical sorting and packaging

The German potato and onion cooperative Groka is located east of Hannover. More than half of Germany’s onions and half of Germany’s potatoes are grown in this area of Lower Saxony. Groka has a share of the German onion market of as much as 20-25%. In the video report below, director Volker Peters explains the entire process including the new Elisam sorting line and the extraction from Jongejans Luchttechniek.
About 20% of the onion volume Groka packs itself (6,000 to 8,000 tons), but the bulk is delivered to packers throughout Germany, from Munich to Hamburg. Onions are packed from 500 grams to 2.5 kilograms, potatoes from 5,000 grams to 25 kilograms. Groka has a central storage facility with a capacity of 25,000 tons, in which its members’ harvests are kept.


In recent years, the cooperative decided to invest in an entirely new optical sorting line in order to continue to serve its customers of the desired quality and to save hands. For this purpose, several projects in the Netherlands and Switzerland were visited. In 2021, for example, a visit was made to Top The Onion Group in ‘s-Gravenpolder to see the same combination of optical sorting technology with Jongejans Luchttechniek’s extraction system.

Extraction plays a crucial role in the performance of an optical sorting line. The sorter has to be located in an almost clinical environment to function optimally. Extraction of skins and dust at an early stage is essential in this regard. Windshifting technology is used to allow the onions to enter the process on the grader as cleanly as possible. To protect the high-tech camera technology and to get the images as clear as possible, overpressure is also used on the camera boxes.

At the same time, Groka has also invested in extraction at the packaging lines, which increases the capacity of the weighing/packaging machines. This additionally ensures a visibly cleaner working environment, free of dust. In total, extraction takes place at 31 points during optical sorting and a further 29 points in the packaging department. Jongejans offers us total solutions for this. The systems have been working here to our complete satisfaction for more than 30 years, says Volker Peters.

In the United States and Europe, another forty large onion processors work on a daily basis to their satisfaction with Jongejans’ extraction solution on the sorting system. Groka is the first German processor to now also work with it. “The beauty of our solutions is that they make everyone who works with them happy. Good extraction ensures better operation of machines, less dust in the room and cleaner products.”

Those interested in looking at Groka may contact Jesse Vonk, please complete the form below for this.

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