Quality Characteristics and Antioxidant Activity of Kalopanax pictus Cortex Tea Depending on the Preparation Methods, Namely: Pan-Roasting and Steaming

Abstract

This study investigated the quality characteristics of tea obtained by the pan-roasting and steaming methods with the aim of increasing the functional effects of substitute tea prepared from the cortex of Kalopanax pictus. After 10 min of steam treatment followed by pan-roasting, the samples from the SKP group had a higher soluble solids content compared to those from the KP group, which underwent pan-roasting without steam treatment. The KP group samples had lower polyphenol content than those of the SKP group and SKP9 (by steamed 10 min and pan-roasting 9 min) showed the highest polyphenol content. Also, the SKP group had higher flavonoid contents than the KP group, with the highest flavonoid content found in SKP9. In the 2,2-diphenyl-1-picrylhydrazyl radical scavenging test, SKP9 showed the highest antioxidant activity. The 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging test showed similar results. The activity tended to increase with pan-roasting along with the steaming method compared to only pan-roasting.