Effect of maltodextrin dextrose equivalent and inlet air temperature on physicochemical properties of barberry fruit powder produced by spray drying

Barberry fruit is rich in terms of nutritional principles such as antioxidants and phenolic compounds, and its powder could also be considered as an important source of these components. Spray drying is widely used to produce beverage powders. The carrier type and inlet temperature of spray dryer are the most important factors affecting the properties of resulted powder. In this study, the physicochemical properties of obtained barberry juice powder (Brixº 12) using 12% (w/v) maltodextrin with dextrose equivalents of 4-7 and 16.5-19.5 were investigated under two input air temperatures of 130 and 150 °C. Results indicated that at the temperature of 130 °C, with an increase in dextrose equivalent, moisture content decreased and bulk density and higroscopisity increased (P<0.05). Glass transition temperature of produced powders, at inlet temperature of 130 °C increased with enhancement of dextrose equivalent. Scanning electron microscopy presented that the bulk density raised with addition of dextrose equivalent. X-ray diffraction verified the presence of amorphous surfaces about obtained powders. Applying of maltodextrin with higher dextrose equivalent caused reduction in total anthocyanin content. The results of colorimetric assessment revealed that with an increase in dextrose equivalent, a* index decreased (P<0.05). Generally, the produced powder using fewer dextrose equivalent, under inlet temperature of 130 °C had better physicochemical characteristics.