Inlet temperature affects spray drying quality of watermelon powder

Abstract

The effect of the inlet temperature on the quality of watermelon powder after spray drying was evaluated. Inlet temperatures of the drying air of 120, 130, 140, and 150°C maintained water solubility of the watermelon powder at 96%. At 253 µM/g, the ORAC value of the watermelon powder dried at 130°C was the highest among all tested powders. The D<sub>50</sub> of the watermelon powder dried at 130°C was 18.21 ± 0.22 µm with a span of 1.73 ± 0.038, which was more uniform than that of other powders. The crystallinity of the powder dried at 130°C was higher than that dried at both 120 and 150°C and showed stronger thermal stability. Moreover, watermelon powder dried at 130°C presented a similar aroma as the fresh watermelon juice when being solved. Hence, an inlet temperature of the drying air of 130°C was the optimal temperature for the production of watermelon powder.