Using the sun to produce high value vegetable products

Solar dryers can reduce the time to dry cabbage or chili by half to three-quarters compared with sun-drying and they are more hygienic. Selling dried chili can earn up to a third more income than selling fresh produce. Dryer designs can include a heating chamber (using charcoal or firewood) for use in the absence of sunlight, or cabinet types with glass-walled drying chambers and were produced in conjunction with the Royal University of Agriculture in Cambodia and the National University of Laos.

Processing Chili (Lao PDR):

  • Sort good quality and damage-free fruit, preferably red-ripe.
  • Weigh fruit.
  • Spread fruit in drying trays and place inside the drying chamber of the solar dryer.
  • Periodically inspect the fruit until the desired moisture content is reached, usually 10% or less (chili may have 80-85% moisture content; if 1 kg fresh chili is being dried, the weight of the dried product at about 10% moisture content would range from 250-300 gm).

Processing Cabbage (Cambodia):

  • Clean cabbage by removing damaged parts.
  • Chop the cabbage into small slices.
  • Place slices in suitable container and add 5% salt solution for overnight incubation.
  • Spread the slices thinly on drying trays and place inside the drying chamber of the solar dryer.
  • Periodically inspect the cabbage slices to determine the desired dried product (same procedure as chili).

Solar drying technique brings direct benefits to farmer

Ms. Khoune, a farmer from Hadxayfong District, Vientiane, Lao PDR, learned solar drying techniques from a mobile training course. She now cleans and sorts chili before sun drying, which helps ensure the quality of her product. She previously sold chili for 15,000 KIP/kg, but now she can sell it for 20,000 KIP/kg, and her dried chili is always in demand. Properly dried chili can be safely stored for up to a year.