Abstract
Coriander (Coriandrum sativum L.) and parsley (Petroselinum crispum L.) are widely used culinary herbs valued for their abundance of bioactive compounds, particularly phenolics and flavonoids, which are responsible for their strong antioxidant potential. Preserving these compounds during post-harvest processing is crucial to maintaining their nutritional and functional properties. This study evaluated the effects of prolonged air drying at a controlled temperature of 20 ºC for 72 h on the antioxidant capacity and physicochemical properties of coriander and parsley, considering both leaves and stems. Samples were analysed at 0, 24, 48 and 72 h of drying for moisture content, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity assessed using FRAP, ABTS, and DPPH assays. Moisture content decreased progressively over time, while both herbs retained significant antioxidant activity even after prolonged drying. Antioxidant capacity reached its maximum around 48 h, likely as a result of concentration effects associated with water loss, followed by a decline at 72 h which may be attributed toto the degradation of thermo-sensitive compounds. Results indicate that moderate drying durations of 24 to 48 h, at 20 ºC, optimize antioxidant retention in both herbs. Prolonged drying beyond this period led to reduced antioxidant capacity, presumably due to degradation of thermo-sensitive phenolics and flavonoids. These findings emphasize the importance of controlling drying duration under mild temperature conditions to preserve the bioactive potential of aromatic herbs. This study provides valuable insights for developing sustainable drying protocols aimed at maintaining the nutritional and functional quality of coriander and parsley.
