Isolation and Physico-chemical Characterization of Triticum Decocum Starch

摘要

Ethiopian oat (Triticum decocum) starch has been isolated and examined for its chemical composition and physicochemical properties. The proximate composition of the starch on a dry weight basis is found to be 0.23% ash, 0.26% protein, 1.54% fat, and 56.31% starch. The total amylose content is 28.4% with 20.11% apparent amylose and 29.19% lipid complexed amylose. SEM showed oval, spherical shaped granules. The particle size distributions of the starch showed monomodal normal particle size distribution with the average volumetric particle diameters being about 23.03 mu m, and specific surface area 0.7186 m(2) g(-1). XRD showed a pattern that is typical of A-type with a distinctive maximum peak at around 17 degrees 2 theta. At all relative humidities, its water sorption properties resemble that of maize starch. It has unique swelling power and solubility in water at different temperatures. Viscosity curves of 10% of starch paste showed a peak viscosity of 1926cP. Its cold paste viscosity and hot paste viscosity are 4236 and 1720 cP, respectively. The breakdown and set back viscosities of Ethiopian oat starch are 206 and 2647cP, respectively. The FTIR showed the characteristic features of prominent starch peaks. Physicochemical characteristics of the oat starch have shown that it has similar properties with maize starch which could make it fit for use in food and pharmaceutical industries, especially in the area where oat is produced as endogenous crop like in Ethiopia.