Evaluation of the Effect of Acetylation and Oxidation on Some Functional Properties of Starch Isolated from Dioscorea dumetorum (Wild)

The starch extracted from the wild species of Dioscorea dumetorum were characterized for ash and moisture content, crude fibre, protein and fat. The modified starches were prepared by pre-treatment of the native starch with alkaline and acidic solution at room temperature prior to modification using hypochlorite for oxidation and acetic anhydride for acetylation. Effects of acetylation and oxidation on some functional properties of the starch were evaluated. Variations were observed in the functional properties of the starch as swelling power ranged from 10.3-10.9, solubility index 6.2-7.6% and apparent amylase content 16.05-21.02%. Oxidized starch showed higher paste clarity than the acetylated and native starches at pH 12. The paste clarity of both native and modified starches were found to be pH dependent. The swelling-power of the native and modified starches put them in the category of highly restricted-swelling starch.Keywords: Dioscorea dumetorum, Starch, Acetylation, Oxidatio

The Effect of Hypochlorite Oxidation and Acetylation on Some of the Physicochemical Properties of Icacina Trichantha Starch

The study evaluated the effect of hypochlorite oxidation and acetylation on some physicochemical properties of Icacina trichantha starch. The native and modified (oxidized and acetylated) starches were studied with respect to Infrared spectroscopy(IR), microscopy, gelatinization, swelling power, solubility index, amylose content, paste clarity and proximate compositions. Oxidized starch had the highest paste clarity, followed by the acetylated starch. The paste clarity of all the starches were found to be pH dependent. The modified starch also had higher solubility index compared to the native starch but lower gelatinization temperature. The modified starches had lower swelling power but higher amylose content. The properties of the starches were found to be dependent on the amylose content.Keywords: Icacina trichantha starch, Oxidation, Acetylation, Physicochemical propertie