Post-harvest grapes are susceptible to fungal infections even if stored at the optimum temperature …

UVASYS Uvasys first launched in the market about 14 years ago and brought about a new, particularly innovative development in the field of laminated plastic sulfur dioxide generating sheets. It became the product of choice in many markets and therefore over the years there has been development of competing laminated plastic sheets. These products are manufactured and printed deliberately to resemble Uvasys. Their performance however is very different. Today, there appear to be 3 “plastic” sheets sold commercially outside of Uvasys. These are: Osku Hellas (manufactured in Chile), Proteku Plus (manufactured in Brazil) and Vinguard (manufactured in South Africa).


Post-harvest grapes are susceptible to fungal infections even when stored at the optimum temperature of -0.5 ° C. The most important pathogenicity of stored table grapes is the “Gray Mold”, commonly known as “Botrytis”, which is caused by Botrytis cinerea. In some countries, particularly in the United States, they disinfect the grapes with sulfur dioxide gas.  However, if the grapes are to be transported over long distances this method is not practical.
Consequently, laminated plastic sulfur dioxide generating sheets were developed to facilitate the transportation and post-harvest storage of table grapes today for periods of up to 4 months. Because of concerns about sulphite residues, there is an ongoing research into finding alternatives. However, the responsible use of Sulfur Dioxide remains the only commercially viable method of storing and transporting table grapes.





  1. Packaging convenience for boxes of grapes.
  2. Lower labor costs.
  3. Cost savings due to the elimination of paper packaging materials.
  4. A uniform distribution of SO2 in the box.
  5. Safety: Chemicals can not be dispersed if the UVASYS sheet is accidentally torn.
  6. Uvasys can be easily adapted to dimensions so as to fit most boxes.
  7. Less damage from SO2.
  8. Predictable and stable emission of gas.
  9. Extended storage periods are possible without any change in the laminated plastic sheets.
  10. As Uvasys does not emit large bursts of gas, in case of disturbance in the cold chain, the grapes are subjected to less damage by sulfur dioxide.
  11. The sheet does not break down in case where the cold chain is interrupted.
  12. Table grapes stored in Uvasys have low residual sulphites (usually <5ppm), in accordance with Directive 2006/52/EC of the European Parliament and of the Council of 5 July 2006 on food additives other than colours and sweeteners.
  13. Same aesthetic appearance before and after use.
  14. The staff unpacking the products is never exposed to high levels of sulfur dioxide gases.
  15. Uvasys contains less plastic than the paper production packaging and disposal is easier.
  16. Excellent appearance of stems and berries.
  17. The storage life of grapes is prolonged.
  18. Given that the sheet is compressed it requires less storage space.
  19. The sheet can be easily repacked in the box, if opened for any reason.
  20. Uvasys sheets do not need to be removed before the container reaches the supermarket.
  21. Strict quality assurance based on performance for each batch.
  22. The Batch Number printed on each sheet allows traceability in case of problems.
  23. Preference of certain British supermarkets for grapes packed with Uvasys.