Effect of inlet temperature on physico-chemical properties of spray dried acid lime (Citrus aurantifolia Swingle) juice powder

This study aimed to evaluate the effect of inlet air temperature (150, 160, 170 and 180 °C) on the physicochemical, reconstitution, functional properties, and powder microstructure (particle size, polydispersity index, and SEM images) of acid lime juice powder at a fixed maltodextrin concentration of 20%. Higher inlet air temperatures notably reduced powder moisture content and water activity (5.85–3.06% and 0.33 − 0.25 a w , respectively), while increasing particle size (267.80-427.40 d.nm) with smoother surfaces, as evidenced by SEM images. Powder yield was highest at 160 °C (16.58%), whereas functional properties such as ascorbic acid (14.77 mg/100 g), total phenol content (78.22 mg GAE/100 g), and antioxidant activity (56.22 mg AAE/100 g) were highest at 150 °C and decreased with increasing inlet temperature. Bulk density, tapped bulk density, particle density and wettability time decreased, while porosity, dispersibility, Hausner ratio, Carr’s index, polydispersity index, and particle size increased with increasing inlet temperature. Among the conditions investigated, an inlet air temperature of 160 °C with 20% maltodextrin was associated with overall desirable powder characteristics under the fixed experimental conditions employed.