This study aims to investigate the effect of different infrared powers (IP)
(38, 50, 62, 74, and 88 W) on drying kinetics, total phenolic content (TPC)
and individual phenolics, antioxidant activity (AA) and antibacterial
activity, and color quality of sage leaves. IP level significantly affected
(p<0.05) drying kinetics and bioactive contents and color quality of sage
leaves. Higher TPC and AA were obtained from the sample dried at 88 W.
Rosmarinic acid, caffeic acid, gallic acid, and luteolin were found as major
phenolic compounds and their higher levels were obtained from the samples
dried at IP level of 88 W. All samples showed antibacterial activity on test
pathogens. A higher correlation was observed between TPC, rosmarinic acid
level, and antibacterial activity (P>0.80). This study suggested that sage
leaves should be dried at 88 W regarding lower drying times and color
changes, lower phenolic degradation, and higher antibacterial activity.