Effects of Spray-Drying Temperatures and Ratios of Gum Arabic to Microcrystalline Cellulose on Antioxidant and Physical Properties of Mulberry Juice Powder

This study aimed to investigate the influences of inlet air temperatures (120 °C, 130 °C, 140 °C and 150 °C, 160 °C) and the ratios of gum Arabic to microcrystalline cellulose on the quality of mulberry juice powder produced by the spray drying process. Determination of moisture content, bulk density, solubility, total phenolic content (TPC), total anthocyanin content (TAC) and antioxidant capacity (AC) of the obtained powders was performed. The study on temperatures showed that all parameters studied were significantly affected by the shift in temperatures. The powder dried at 160 °C had the highest TPC (38.32 ± 0.36 mg GAE/g DW) and water solubility index (78.70 ± 0.75%); however, it had the lowest moisture content (3.90 ± 0.14%) when compared with the samples dried at other temperatures. Meanwhile, at 140 °C, powder samples with the highest TAC (4.690 ± 0.18 mg cyd-3-glu/g DW) and highest AC (648.09 ± 22.98 µmol TE/g DW), respectively, were obtained. Increasing microcrystalline cellulose and decreasing gum Arabic contents in the carrier mixtures showed significant decreases in moisture content, bulk density, solubility, TPC, TAC and AC