The phenolic compounds in RBE or CDRBE (protocatechuic acid,
vanillic acid, p-coumaric acid, ferulic acid and sinapic acid) were
prepared in model system experiments at the same concentration
of RBE and CDRBE from HPLC analysis results. The phenolic compounds
were evaluated for their inhibitory effect on potato and
apple PPO as described in the method 2.4.