Impact of traditional and innovative technologies on some characteristics and bioactive compounds of Opuntia macrorhiza juice

Abstract

AbstractIn addition to flavonols and the high contents of betacyanins, O. macrorhiza fruit is rich in vitamin C. Different pre- extraction techniques were used aiming at increasing bioactive compounds and yield of O. macrorhiza juice. In comparison to untreated fruit's mash, the mash was treated prior to pressing with four pre-extraction techniques, (1) pulsed electric field (PEF), (2) thermal treatment using microwaves, (3) enzymatic treatment with commercial pectolytic enzymes, and (4) a combination of thermal and enzymatic treatments. The mashes treated enzymatically or by combination of thermal and enzymatic treatments produced higher yields of the juice. Although all treatments led to no significant differences in total content of betacyanins, all treatments provided significantly higher contents of flavonol glycosides compared to the untreated mash. Subsequently, the juice was preserved by three preservation technologies: Pulsed Electric Field (PEF), High Hydrostatic Pressure (HHP), and Pasteurization. Antioxidant activity of pasteurized juice was slightly lower than juices preserved by PEF and HHP techniques