Native cassava starches isolated from three varieties (TME 419, TMS 98/0505 and TMS 98/0581) were acetylated at different concentrations of acetic anhydride (10, 15, 20, 25 and 30%).Effect of the concentrations was evaluated on properties of the starch like bulk and tapped densities, morphology, degree of whiteness, water absorption and hydration capacities, paste clarity and freeze thaw stability. Bulk density values for native starches ranged between 0.27 and 0.30 g/ml while the values for acetylated starches ranged between 0.37 and 0.48 g/ml. Tapped density values ranged from 0.34 to 0.38 g/ml and 0.53 to 0.63 g/ml (for native and acetylated starch samples respectively). Acetylation did not affect the shape and granular structure of the starches. Degree of whiteness ranged from 93.10 – 95.30% and 93.50 – 96.63% for native and acetylated starches respectively. Water absorption and hydration capacities were significantly reduced by acetylation and paste clarity ranged from 16.78 – 26.28% and 20.50 – 30.96% for native and acetylated starches respectively. Degree of acetylation ranged from 0.81 to 3.08%.Acetylation enhanced the functional characteristics of cassava starches and these are good pointers to the possible utilization acetylated cassava starches in different food applications thus widening its utilization in Nigeria.

Keywords : Cassava starch, acetic anhydride, acetylated starches, physical and functional properties.