Retention of polyphenolic species in spray-dried blackberry extract using mannitol as a thermoprotectant

Influence of spray drying on bioactive compounds of blackberry pulp microencapsulated with arrowroot starch and gum arabic mixture

The objective of this research work was to obtain blackberry pulp in microencapsulated powder with a of arrowroot starch/gum arabic mixture by spray drying. Experimental design, with 11 runs, was performed to evaluate the effects of inlet air temperature (100-150 °C) and encapsulating agent concentration (1:0.5-1:2, blackberry pulp solids: arrowroot starch/gum arabic) on the functional properties of powders. The ascorbic acid content and luminosity of the powder increased with increasing encapsulating agent concentrations, whereas the b* values decreased. Increasing the inlet air temperature and decreasing the encapsulating agent concentration, the content of anthocyanins also increased. The powders were able to reduce Fe⁺³ and to trap free radicals, showing antioxidant property. The temperature of 143 °C and concentration of encapsulating agent 1:1.78 were the ideal conditions to have high content of ascorbic acid and good content of anthocyanins and antioxidant properties.

Microencapsulation of blackberry pulp with arrowroot starch and gum arabic mixture by spray drying

This research work aimed to obtain blackberry pulp powder by spray drying and, by an experimental design, evaluated the effect of inlet air temperature (100-150 °C) and blackberry pulp solids:arrowroot starch/gum arabic solids ratio of 1:0.5-1:2 on the physicochemical properties of the powders. Arrowroot starch and gum arabic present glass transition temperature (Tg) values above 100 °C; hence it was possible to employ them as carriers in blackberry pulp spray drying in order to increase Tg of the system. Powder yield and solubility increased with increasing blackberry pulp solids:arrowroot starch/gum arabic solids ratio of 1:0.5-1:2, whereas hygroscopicity decreased. Yield, solubility and hygroscopicity of the powders increased and water activity decreased, with increasing inlet air temperature. The powders presented low moisture content and water activity. Temperature of 143 °C and blackberry pulp solids:arrowroot starch/gum arabic solids ratio of 1:1.78 were the optimal conditions to obtain high yield and blackberry powders that are soluble in water and less hygroscopic.