Sun – Dried Tomatoes

At Neo Erasmio/ Xanthi, Geothermica Hellas Ltd has created a model drying plant for the production of dried tomatoes. The tomatoes are carefully selected from stringently quality-controlled fruit grown on the fertile plains around the Nestos River Delta, and are dried at moderate temperatures using geothermal energy. Before drying, each tomato undergoes an elaborate process of pre-washing, washing, sorting and cutting.
The drying process is carried out in tunnel ovens with a total fresh fruit capacity of 10,000 kg. The hot air, which is not recycled, is introduced into the ovens in a continuous flow with a renewal rate of 700 times per hour. The air is heated to 55-58°C by geothermal fluids (from a borehole 300 metres deep) circulating in tube-type heat exchangers. The tomatoes are batch-dried, not belt-dried, with the raw fruit loaded on stainless steel grill trays.

This method, with its particular thermodynamic characteristics:

  • avoids the thermal shock that affects the cell structure of the dried product
  • preserves the original colour of the fruit
  • preserves the intense natural flavour that makes these tomatoes ideal for all uses
  • no salt and no preservatives are added
  • are packaged in vacuum-seated with added nitrogen

With this soft-technology method all the fundamental characteristics of the tomatoes are preserved unchanged: their deep red colour, their intense aroma and their genuine flavour. It does not destroy the lycopene that is responsible for their rich red colour and is held to be one of the tomato's most important nutritive elements. The final product is kept in cold storage and packaged without the addition of preservatives. Tomato products are marketed under the label Geothermiki Hellas. The whole production and standardisation system is ISO 22000 certified.
The above is an extract from the article "USE OF GEOTHERMAL ENERGY FOR TOMATO DRYING", which was published in the quarterly Newsletter of "GEO-HEAT CENTER", from the University of Oregon, USA.