Evaluation of Different Methods for Betanin Quantification in Pitaya (stenocereus Spp.)

Spectrophotometry UV-Vis, with calibration curve (SWCC), High-performance liquid chromatography (HPLC), and Spectrophotometry with an extinction coefficient (SWEC) were used for betanin quantification in pulp and peel of pitaya (Stenocereus spp). The concentrations of pulp betanin measured by the three analytical methods did not differ significantly, as assessed by the Scheffe method (P > 0.05). The mean of pulp betanin was 2.092 mg/g dry sample. With respect to the peel samples, there was a significant difference: a lower betanin concentration was obtained by HPLC. Since the SWCC method required a standard solution, and that HPLC was time-consuming, the SWEC method represented the best choice for betanin quantification in pulp in order to reduce cost, time, and wastes.