Effect of microbial polyphenol oxidase on the color of infused black tea.

The authors have studied methods of im-proving the flavor and color of infused black tea with microbial polyphenol oxydase (MPPO). The addition of 0.1% MPPO to black tea during the manufacturing process led to a shortening in fermentation time and increased its color during infusion. A significant increase in theaflavin and thearubigin contents was observed in infused MPPO-treated black tea.