AMYLOSE CONTENT AND SOME FUNCTIONAL PROPERTIES OF MICROWAVED SORGHUM STARCH

`ABSTRACT The study was to investigate the effect of microwave heating on the functional properties of sorghum starch. Sorghum grains were sorted and steeped in water and NaOH for 48h, washed in water and NaOH for 48h, wet milled, mixed and filtered, wet starch was rewashed in NaOH, decanted and centrifuge at 3000rpm for 20min, the starch was dried at 40℃, milled sieved and packaged. The sorghum starch was divided into three, the first was the control (A), the second was microwave at 2min (B), the third was microwaved at 5min (C). The samples were analysed for Water Absorption Capacity (WAC), Oil Absorption Capacity (OAC) Swelling Capacity (SC), Solubility (S) and least gelation concentration (LGC). All the analysis were evaluated using standard procedures. WAC, OAC, and SC range from 1.80 to 1.97ml∕g, 1.97 to 2.07g and 3.0 to 3.70g respectively. The solubility mean value was constant for all sample, and for LGC, sample A are all viscous and sample B and C form gel from 4% concentration. Microwave treatment increases the water absorption capacity of the sorghum starch but have no effect on the solubility. The oil absorption capacity and swelling capacity initially increase and later decrease with microwave treatment. Amylose content of the sorghum starch increases at the increase in microwave treatment concentration (2%). Short-term microwave treatment can be used as an effective strategy to improve the functional properties of sorghum starch. Sample A can be recommended for consumers since it microwave treatment improve the sorghum starch.