Chiral separation of catechin and epicatechin by reversed phase high-performance liquid chromatography with β-cyclodextrin stepwise and linear gradient elution modes

•Catechin and epicatechin were enantioseparated by HPLC with aqueous β-CD eluents.•Ten catechins were separated by HPLC with an aqueous β-CD linear gradient elution.•Catechins in a green tea infusion were separated by the present method.•Epimerization of (+)-catechin was suppressed by addition of D-fructose.