Enhancing betacyanin stability: Comparison of dragon fruit (Hylocereus polyrhizus) pulp and peel powders through encapsulation technology during storage

Abstract

Betacyanin can be found in the peel or pulp of dragon fruit. As a natural pigment, betacyanin is unstable, so it requires encapsulation technology to maintain its quality. The stability of encapsulated betacyanin from dragon fruit peel compared to dragon fruit pulp has yet to be discovered. This study aims to compare the stability of encapsulated betacyanin (with maltodextrin and gum Arabic) from dragon fruit peel and pulp dried with vacuum drying. Dragon fruit peel extraction utilized a 50% aqueous ethanol solvent, while pulp juice extraction was performed. The ratio of dragon fruit extract to coating materials was set at 1:3 (solid/solid). Research shows that dragon fruit juice powder had higher stability and phytochemical concentrations than the ethanol extract of dragon fruit peel powder during 30 days of storage. Despite similar color stability (similar range value of ΔE), the color from dragon fruit juice powder more closely resembled the natural fruit, albeit with weaker antioxidant activity than the peel powder. Betacyanin concentration in juice powder was notably higher (82.56–156.82 μg/g) than in the ethanol extract of dragon fruit peel powder (52.51–75.12 μg/g). A combination of maltodextrin and Arabic gum (1:1) as coating materials demonstrated the highest concentrations of total phenolic and total betacyanin (81.15–95.87 mg/g and 121.91–156.82 μg/g, respectively) during the storage period. These findings contribute to our comprehension of betacyanin stability and functionality, facilitating precise applications in industrial processing environments based on their source attributes.