Potential Use of Selected Sweetpotato (Ipomea batatas Lam) Varieties as Defined by Chemical and Flour Pasting Characteristics

Agnes Nabubuya, Agnes Namutebi, Yusuf Byaruhanga, Judith Narvhus, Trude Wicklund

Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Aas, Norway.
Department of Food Technology and Nutrition, Makerere University, Kampala, Uganda.

DOI: 10.4236/fns.2012.37118                

Abstract

Chemical and functional properties of ten sweetpotato varieties were investigated. The sweetpotato were of various flesh colours which included orange, yellow, cream and white with dry matter content ranging from 30.2% - 39.2%. The sweetpotato varieties varied significantly (p < 0.05) in total amylase activity, total starch and amylose content whose value ranges were 0.256 - 0.570 mg/ml/min 68.4% - 73.6%, 16.2% - 23.4% respectively. The pH of flours from the different sweetpotato varieties ranged from 6.01 - 6.64. The pasting behaviours of the sweetpotato flours also showed significant differences (p < 0.05) in the individual parameters (peak time, pasting temperature, peak viscosity, trough viscosity, final viscosity, breakdown and setback) among the different varieties. The results revealed the influence of variety on the chemical composition of sweetpotato and their pasting properties. Correlations were also revealed among different components of the sweetpotatoes which would be a basis in selection of the varieties for processing into different products.

Keywords

Sweetpotato; Chemical Properties; Pasting Characteristics

Conflicts of Interest

The authors declare no conflicts of interest.

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