STARCH RELATED CHANGES IN STORED SOFT SORGHUM PORRIDGE

Soft sorghum (Sorghum bicolor (L.) Moench) unfermented porridge was pr epared by cooking pearled sorghum flour (6% solids in water) in a micr owave oven. Fermented porridge was prepared by mixing with Lactobacill us delbruekii for 12 hr at 48 degrees C, followed by cooking. Porridge was aged (0-12 hr) at 25 degrees C or 7.5 degrees C. Starch polymer s olubility was determined by high performance size exclusion chromatogr aphy (HPSEC) and theology followed with a rotational viscometer. Durin g aging, solubilized and gelled amylose and amylopectin retrogradation rates were higher in porridge stored at 7.5 than at 25 degrees C. Amy lose polymer solubility decreased with storage, while solubilized amyl opectin remained in solution. Fermented porridges were lighter in colo r and their initial consistency indexes increased faster. HPSEC of sol uble polymers was more sensitive than enzymatic starch digestion.