These FOG compounds were qualified on both UHPLC and HPLC, and this
UHPLC method successfully separated rutin (quercetin-3-O-rutinoside) and K-grg (kaempferol-3-O-glucorhamnoglucoside) while conventional HPLC method did not. The total amounts of FOG compounds in
the tea samples were 2.32–5.67 g/kg dry weight