AbstractAn improved method is described for the characterization of phenolic compounds using post‐column shift reagents following their separation by high performance liquid chromatography (HPLC). Modifications include the use of NaOH to adjust the pH of the column effluent, prior to introducing the AICI3and H3BO3reagents, and the use of commercially available spin chambers for efficiently mixing the effluent with the reagents, resulting in a negligible loss of resolution. Shifts obtained by the HPLC post‐column derivatization and the conventional procedure are compara