Instant Controlled Pressure Drop‐Assisted Extraction of Betalains From Dragon Fruit ( Hylocereus undatus ) Peel

ABSTRACT The peel of the dragon fruit ( Hylocereus undatus ) is one of the most important sources of betalains, water‐soluble pigments with interesting biological and functional properties. Instant controlled pressure drop (Détente Instantanée Contrôlée, DIC) is a process that involves high pressures for short times and an abrupt pressure drop to increase the extraction yield of bioactive compounds. Therefore, this study aims to evaluate the DIC technology to improve the recovery of betalains from dragon fruit peels. The peels were processed with DIC using a central composite design whose independent variables were pressure (0.10–0.30 MPa) and time (5–45 s). The design consisted of 13 treatments with 4 factorial points (2 2 ), 4 axial points (− α , −1, 0, +1, and + α ), and 5 central points (0, 0). The peel untreated was used as a control. Betalains were then extracted with acidified water and quantified by UV–visible spectrophotometry and HPLC. The functional groups of the pigment structures were analyzed by FTIR and their color parameters measured. The results showed a significant increase in betalain recovery. Treatment with DIC at 0.27 MPa for 11 s allowed the recovery of 171.96 ± 2.55 mg of total betalains, corresponding to an increase of 46.96%. Moreover, no significant changes were observed in the functional groups, indicating the preservation of the stability of the pigments. Finally, the DIC treatment improved the color properties of the extracts. This study demonstrates the potential of DIC to increase betalains extraction from dragon fruit through an environmentally friendly process.