Effects of Pneumatic Conveying Drying Conditions on Damaged Starch Content and Particle Size of Cassava Starch

This research aimed to investigate the effects of pneumatic conveying drying conditions on damaged starch content and particle size of cassava starch using response surface methodology. Three parameters of interest, i.e. drying air temperature (120, 160, and 200 degrees C), drying air velocity (20, 30, and 40 m/s), and feed moisture content (40, 50, and 60% d.b.), were varied. Experimental results showed that damaged starch content and average particle size of cassava starch before drying were approximately 0.45% and 21.47 mu m, respectively. However, after drying, the values were altered to approximately 0.69 to 6.84% and 15.40 to 31.67 mu m, respectively. The drying air temperature, drying air velocity, and feed moisture content significantly affected the changes. The results indicated that cassava starch granules were damaged and then agglomerated into large particle during pneumatic conveying drying depending on operation conditions.