ABSTRACT

This research aimed at providing a non-food source of starch that can be used in food and industrial application. It will reduce competition for use of sources of food for Starch by man resulting in high demand with consequent economic implications. In this work starch from Icacina trichantha tubers (under-utilized crop) were isolated and the purity level determined. The native starch was chemically modified using acid (HC1), alkaline (NaOH) and oxidized using H202. Functional properties, pasting properties and photomicrographs of the starch samples were analysed. Bulk density of native and modified starches ranged from 0.56 to 0.78; pH 3.50 to 8.86; Gelatinization temperature 60 to80; Water holding capacity 64.0 to 72.0; swelling power 6.71 to 10.71; wettability 07.47 to 18.94; solubility 14 to 37. The peak viscosity ranged from 143.0 to 2965.0 RVU. The native starch had the highest peak viscosity at a temperature of 84.10°C in 4.53 mm and acid modified had the lowest at 85.70°C in 4.33 mm. The breakdown viscosity ranged from 120.0 to 1291.0 RVU with the alkaline modified starch having the highest and acid treated had the lowest. The final viscosity ranged from 81.0 to 2066.0 RVU. Alkaline treated starch had the highest value while acid treated starch had the lowest value. The setback viscosity ranged between 58.0 and 737.0 RVU with the alkaline treated starch having the highest value and acid treated starch having the lowest value. The pasting temperature ranged from 84.10 to 85.90°C. The photomicrographs showed that the starch granule in all the samples had irregular shape, generally small to medium sized with sizes ranging from 30 to I l0nm and granular frequency ranging from 45 to 183. Icacina trichantha starch resembled conventional food starches, and will compete favourably with them in food system as an industrial starch