AMobile Minor concurrent flow spray dryer (Niro, Copenhagen,
Denmark), equipped with a rotating atomizer nozzle (TS-Minor,
M02/A) was used to dry the mucilage. The diameter of the drying
chamber was 800mm×620 mm/cone 60◦. The mucilage was fed
into the drying chamber using a peristaltic pump (Watson-Marlow
505S/RL). A 23 factorial design with three central points was used to
evaluate the effect of the independent variables: inlet air temperature
(130–170 ◦C), feed flow rate (2.3–3.3 L/h) and atomizer speed
(21,000–24,000 rpm) on the powder properties. Drying air flow
rate was fixed at 84±2 kg/h. Distilled water at room temperature
was used for start-up and shut down operations. The experimental
design matrix is shown in Table