ISOLATION AND ACETYLATION OF STARCH USING ETHANOIC ACID FOR INDUSTRIAL USES

Abstract

Starch from Cassava and Potato was isolated using non-conventional method and reagents. The isolated starch was chemically modified using ethanoic acid via acetylation and the success of the modification was evidenced by the changes observed on the functional properties such as, solubility, swelleability and film formability. The solubility of acetylated starch was found to vary with increase in acetylation time at constant temperature. FT-IR analysis further proved the success of the modification reaction from the following peaks 2926-3022 (−C─H stretch of aliphatic (−CH₃) of acetyl group), 1381-1402 (−C−CH₃) deformation in acetyl), 1030-1068 (C−O) stretching vibration in acetyl) and 1739, for carbonyl (C=O). Ash, carbohydrate, energy value, crude protein, phosphorus (P), potassium (K), sodium (Na), and calcium (Ca) of isolated Cassava starch were higher than those obtained from isolated potato starch. However, moisture and fat contents of isolated potato starch were higher than cassava starch although the crude fiber for both starches isolated was significantly similar. The prepared starch acetates gave low water swelleability and solubility making them good candidates for use in food such as stickening agents, thickeners and stabilizers in ice cream yoghurts etc. This research has shown the usefulness of the method adopted for starch extraction and the potential of using ethanoic acid as an acetylation agent