Plasma technology protects pears against rot

Retailers are looking at the quality of the fruit they're putting on shelves with an increasingly critical eye, and are quicker to reject it if it has a mark. For that reason, growers are applying a protective coating to increase shelf life, but that doesn't hold sufficiently yet. Jan Hoefnagels of Agrotrade De Leye bv is using TNO knowledge on plasma technology, not just to get pear coatings to hold better, but also to remove fungi. 'The patent application has already been sent.'

A plasma is an ionized gas, also called the fourth state of matter besides solid, liquid and gas. A cold and atmospheric plasma can be generated using a strong electric field. Remarkable results can be achieved by then bringing foils or textiles into contact with the plasma. For instance, plasmas are able to oxidise away bacteria and contamination, or alter the surface characteristics of materials in such a way that other substances are better able to bond with them.

Protective coating
That last property gave Jan Hoefnagels of Agrotrade De Leye bv an idea: 'The coatings that give pears a longer shelf life, should hold even better. I wondered whether plasma technology could solve that problem, and found out at TNO that a lot more was possible. TNO has a technology with which you can bring substances to the plasma state at room temperature, under normal pressure and very energy-efficiently, and they also know which settings you can use for disinfecting fruit, for instance. The people I dealt with were experts who immediately showed interest in my plans. Together with other companies and TNO, we have formed a successful Technology Cluster. I have now applied for a patent, and am working with a machine builder on a device that can pre-process tonnes of pears with plasma technology each day.'

Fewer rejections
By killing fungi, the innovative machinery significantly slows down rotting of pears, and Hoefnagels expects retailers will need to reject less fruit: 'From organic growers in particular, who do not use pesticides. For them it's important that this is a technology where no chemical residue or waste is produced. You can also treat other fruits with it, such as apples, strawberries or raspberries. It's possible that there are opportunities in bulb cultivation, which also has to cope with losses due to bacteria and fungi causing rot.'

Industry and healthcare
Plasma technology can be used in many areas, André Schilt of TNO adds: 'The pesticides that fruit growers do use, can possibly be removed through plasma treatment. A plus, because large retailers are also getting more picky in that respect. There are also numerous possibilities outside of fruit cultivation, for instance in industry or healthcare. Anyone who wants to know more, can download our flyer or contact me.' Hoefnagels thinks that's a good idea: 'I hope many more SMEs will find their way to TNO.'

For more information:
De Leye Agrotrade BV
www.bio-fresh.nl
André Schilt can be reached at:
T +31 88886 61354
E andre.schilt@tno.nl

The flyer on plasma technology can be downloaded from: www.tno.nl/plasma