Figure 5.

Changes in (a) total polyphenol content and (b) DPPH radical scavenging activity of OFG and TFG under each optimal fermentation condition. ●: Blank (non-inoculated green tea with no supplementation), ■: OFG (one-step fermented green tea under optimal fermentation conditions), □: TFG (two-step fermented green tea under optimal fermentation conditions). Two-step fermentation of green tea consisted of lactic acid fermentation followed by acetic acid fermentation. For lactic acid fermentation, conditions optimized in a previous study (Jin et al., 2021) [14] were used. Error bars indicate standard deviations determined from triplicate experiments.