Effects of different drying methods on chemical compositions, antioxidant activity and anti-α-glucosidase activity of Coreopsis tinctoria flower tea

Coreopsis tinctoria (CT) flower is widely consumed as flower tea with many good healthcare benefits in China, and room drying is the most common drying method of CT, while many rapid and controllable modern instrument drying methods have been used for the drying of flowers teas. In the present study, effects of drying methods on chemical components, antioxidant activity and anti-α-glucosidase activity of CT have been compared to search for proper drying methods. In the results, drying methods have significant effects on the chemical composition, antioxidant activity and anti-α-glucosidase activity of CT. Vacuum drying at 50 °C, hot air drying at 30 °C and hot air drying at 50 °C are the top three drying methods to produce dried CT of high quality, and hot air drying at 30 °C is more energy-efficient and time-saving. Our results provide some new choices for CT in the future.