Colour and flavour changes during osmotic dehydration of fruits

摘要

Andes berry (Rubus glaucus Benth.) and tamarillo (Solanum betaceum Cav., dark-red strain) fruit were separately submitted to osmotic dehydration with three different osmotic agents: sucrose (70%), sucrose (70%)-glycerol (65%) 1:1, and ethanol. This process decreased the water activity in the fruits and promoted the transfer of main pigments (anthocyanins) and flavour constituents to the osmotic solutions. Tristimulus colorimetry was applied to qualitatively evaluate the process of obtaining colour- and flavour-enriched osmotic solutions. It was found that after successive DIS (Dewatering-Impregnation-Soaking) cycles, it is advisable to obtain high Cab colour parameter values, as criteria for the evaluation of osmotic solutions. Based on colour parameters, anthocyanin content, and volatile analysis, the ethanol and sucrose osmotic solutions from Andes berry were selected as promising raw materials for developing natural additives..