The effects of steaming and roasting temperature and time on mallotus bark (Mallotus japonicus) tea leaves

Abstract

  The effects of steaming and roasting temperature and time on mallotus bark (Mallotus japonicus) tea leaves were investigated. The characteristics we analyzed were color tone, soluble polyphenol content, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical capture activity. We observed that roasting had greater effects on tea leaves than did steaming. We concluded that the suitable roasting temperature was below 200°C for ensuring ideal soluble polyphenol content and DPPH radical capture activity. For optimal color fading, the suitable roasting temperature was below 150°C.