EFFECT OF EXTRACTION METHODS ON FUNCTIONAL AND PHYSICOCHEMICAL PROPERTIES OF RICE AND WHEAT STARCH

This study was aimed to investigate the impact of starch isolation methods from wheat (Buhooth 22) and rice (Anbar ) on the chemo physical , functional properties and final yield of starch .The starch isolated from wheat using three different methods (Dough ball (DB),Batter method( BM) , Alkaline method),and from rice using Alkaline extraction (NaOH 0.15%) .The obtained results showed that the yield of the isolated starch for wheat ranged from (42.6-63.0)% ,and the highest percentage achieved using alkaline isolation (NaOH 0.15%) was 61% and 63% for DBS , As for rice the highest yield was 72.30%,while the lowest yield for wheat using alkaline solution (0.50% NaOH) was (42.6)% . Amylose percentages in wheat starch reached to 55.3% in case of using 0.10% NaOH and it dropped gradually with increasing the NaOH concentration .The resistant starch percentages ranged from (0.06-0.73)% in the starch samples with significant difference among the isolation methods and also between rice and wheat samples .The results of SEM revealed that the isolation methods influenced the starch granules morphology and the chemical and functional characters as well.