A comparative study of the purification of betanin

► Seven methods were tested for the purification of betanin from complex matrices. ► Adequate quantification of betanin by UV-Vis absorbance depends on the source. ► Betanin was purified from fresh beetroots by two different methods (99%+). ► Isobetanin has the same size, but a slightly lower dipole moment, than betanin.