ISOLATION AND PHYSICOCHEMICAL CHARACTERIZATION OF FONIO (DIGITARIA-EXILIS STAPF) STARCH

Fonio (Digitaria exilis Stapf) starch was isolated from the seeds of t wo varieties denominated Hothia and Koulli and its physicochemical pro perties were compared with those of commercial wheat starch. Fonio sta rch granules seen under a SEM had polygonal shapes and small size (abo ut 8 mu m). Amylose content of Hothia (22.6%) was significantly lower than that of Koulli and wheat (26.1% and 25.0%, respectively). There w as not any significant difference in lipid content of fonio starches ( 2.8% and 2.9%), whereas significant differences were observed in their water binding capacity (88% and 80%). Protein and ash were also deter mined. The swelling power and solubility of wheat and fonio starches w ithin the 50 degrees C-90 degrees C temperature range were also studie d. Brabender amylograms of 5% fonio starch slurries showed similarly s haped, single-step curves. However, the two fonio varieties reached qu ite different viscosity values during the heating and cooling cycle.