EFFECT OF CHEMICAL MODIFICATION ON THE FUNCTIONAL PROPERTIES OF CASSAVA STARCH (MANNIHOT ESCULENTA)

Abstract

This study assessed and compared the functional properties from modified cassava starches which include ash content, pH, moisture content, gelatinization temperature, swelling temperature, swelling power, swelling volume and solubility with native starch. The modified starches showed great improvement in gelatinization temperature from starch modified with sodium acetate, ammonium phosphate, sodium acetate neutralized with fumaric acid and sodium acetate neutralized with adipic acid having the values of 790C, 750C, 710C, 720C respectively as compared with 680C of the native starch; solubility values of 66.7%, 39.1%, 22.4% and 37.06% respectively as compared with 0% of native starch; pH values of 7.54, 7.13, 7.05, 7.01 respectively compared with 5.41 of native starch; moisture content values of 11.45%, 13.05%, 14.35%, 13.50% respectively compared with 10.00% of native starch. However, modified cassava starches showed decrease in ash content with values of 0.03%, 0.12%, 0.18% and 0.04% respectively compared with 0.75% for native starch. Finally, modified starch had a swelling power value of 1.23, 3.76, 3.57, 4.00 compared with a value of 8.40 for native starch, and swelling volumes of 1.0, 4.5, 4.2, 5.0 compared with native starch value of 10.5. Therefore, it was noted that the modified starch of Manihot esculenta had several improved functional properties which makes it more desirable for specific industrial uses when compared with the native starch of low quality.