EFFECT OF STARCH ISOLATION METHODS ON CHEMICAL, FUNCTIONAL AND STRUCTURAL PROPERTIES OF PEARL MILLET STARCH (PENNISETUM TYPHOIDIUM)

The study was carried out to determine the chemical, functional, and structural properties of starch that was isolated by various methods from pearl millet (Pennisetum Typhoidium). Isolation methods of starch with different chemicals influenced starch properties. Pearl millet starch was isolated by Sodium azide (alkaline) (T₁), Sodium metabisulfite & lactic acid (T₂) (neutral), and Mercuric chloride (acidic) (T₃). Chemical and functional properties were observed. T₁ yielded a higher amount of starch (56.3 /100g) (db) compared to T₂ and T₃. Proximate analyses of starch showed that the protein content was 0.21 – 0.31%, apparent amylose was 19.42 – 21.60%; however, similar values were observed in fat (0.01%) and ash (0.05%). The swelling power and solubility of the isolated starches differed significantly. The crystalline degree of pearl millet starch of T₁ T₂ T₃ was 37.91, 29.22, and 19.92%, respectively. The result showed that isolation methods brought changes in yield, chemical, and functional properties of pearl millet starch. Starch isolated with alkaline had a higher amount of yield, apparent amylose, and total starch content compared to starch isolated with neutral and acidic solutions.