ISSN 2756-343X
Global Journal of Food and Agribusiness Management ISSN 2756-343X Vol. 2 (5), pp. 001-009, May, 2011. © International Scholars Journals
Full Length Research Paper
Physicochemical and pasting properties of starch extracted from eleven sweetpotato varieties
M.Tsakama1, 2, A.M. Mwangwela2, T.A. Manani2 and N.M. Mahungu3
1University of Malawi, Polytechnic, P/Bag 303, Blantyre 3, Malawi
2University of Malawi, Bunda College of Agriculture, P.O Box 219, Lilongwe, Malawi
3IITA/SARRNET, P.O Box 30258, Lilongwe 3, Malawi
Accepted 21 March, 2011
Abstract
Physicochemical and pasting properties of starch extracted from eleven sweetpotato varieties were evaluated. Relationships between starch properties were determined using correlation analysis. Significant differences were revealed among the physicochemical properties such as amylose, pH, granule size and size distribution. According to the Rapid visco analyzer (RVA) viscosity profiles, all starches exhibited a type A profile which is characterized by high peak viscosity followed by major breakdown. However, significant differences were observed in individual pasting parameters such as pasting time, hot paste viscosity, cold paste viscosity, stability ratio, setback ratio and breakdown. The results revealed that variety has an effect on composition and pasting properties of sweetpotato starch. Correlations developed in this study were useful in predicting starch functionality when applied in food industry.
Keywords: Sweetpotato starch, physicochemical, pasting, viscosity.