Effect of UV-C Light and Hot Air Oven Drying on Qualities of Red Chili
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Abstract
Dehumidification of fresh chili by a hot air oven at high temperatures has a degrading effect on both the physical and chemical properties of dried chili, whereas using low temperatures requires a longer drying time. UV-C irradiation is effective in destroying microorganisms. Therefore, this research aimed to investigate the effect of dehumidification using a hot air oven at 38-40°C combined with UV-C irradiation at 10 and 20 minutes, focusing on the quality and storage characteristics of dried chili. The results showed that the drying time of UV-C-irradiated samples was shorter than that of other treatments. Moisture content and water activity in dried chili increased during storage. L*, a*, and b* skin color values of all treatments decreased over time. UV-C irradiation for 10 or 20 minutes had no effect on pH and titratable acidity values; however, storage caused a decrease in pH and an increase in titratable acidity. Mold and yeast counts were reduced after drying with UVC irradiation and remained undetectable after 120 days of storage.
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