Combination Effect of Germination and Fermentation on Functional Properties of Sorghum Flour
Abd Elmoneim O. Elkhalifa *
Lehrstuhl für Biochemie, Universität des Saarlandes, Campus B2 2, 66123 Saarbrücken, Germany and Ahfad University for Women, Omdurman, Sudan.
Rita Bernhardt
Ahfad University for Women, Omdurman, Sudan.
*Author to whom correspondence should be addressed.
Abstract
Aims: To understand the effect of the combination of the two traditional Sudanese processing methods, germination and fermentation, on the functional properties of sorghum flour.
Study Design: Factorial Experimental design.
Place and Duration of Study: Lehrstuhl für Biochemie, Universität des Saarlandes, Saarbrücken, Germany between May 2015 and July 2015.
Methodology: Fetarita sorghum was germinated for three days, and then the flour obtained was fermented for 8 h. The functional properties of produced flour were studied and ungerminated, and unfermented flour was used as a control.
Results: The germinated-fermented flour has low pH and high titratable acidity. The proteins of the germinated-fermented flour were more soluble in different buffers than the control. Germinated-fermented sorghum flour had the least gelation concentration of 8% compared to 18% for the control. Germination and fermentation significantly (P ≤ 0.05) decreased the bulk density (loose and packed), water and alkaline water capacities. A significant increase in the oil binding capacity, emulsifying activities and stabilities, foaming capacity, foaming stability and wettability was reported in the treated flour. The produced flour has high dispersibility at all pH tested, and high dispersibility was observed at the alkaline pH. SEM results of the germinated-fermented flour support the development in functional properties.
Conclusion: Combination of germination and fermentation improves the functional properties of sorghum flour. This could help anticipate end-product quality and more applications in gluten-free products based on sorghum flour.
Keywords: Sorghum, germination, fermentation, functional properties, SEM