Amylose and amylopectin molecular fractions and chain length distribution of amylopectin in 12 varieties of Ghanaian sweet potato (Ipomoea batatas) flours

Abstract

Sweet potato (Ipomoea batatas) is a commonly cultivated root crop in tropical and subtropical regions, including Ghana. Different varieties of sweet potato have been bred, in order to expand its utilisation within the food and industrial sector. This study analysed flours made from 12 recently developed Ghanaian sweet potato varieties in terms of their amylose and amylopectin molecular fractions and amylopectin chain length distribution. Starch content of the sweet potato flours ranged from 49 to 77 g/100 g dry matter, with 11 of the varieties containing above 60 g/100 g dry matter. An orange-fleshed variety, Apomuden, had the lowest amount of starch (48.9 g/100 g dry matter), while the cream-fleshed variety Histarch had the highest (77.3 g/100 g dry matter). The flours from the 12 sweet potato varieties had intermediate amounts of amylose, within the range 10-30 g/100 g dry matter, and showed typical molecular distribution according to size-exclusion chromatography (SEC). The fine structures of amylopectin, as revealed by anion-exchange chromatography, contained features common for starches of C-type X-ray pattern, but some structural differences were also observed.

Keywords

Sweet potato; Flour; Amylose; Amylopectin; Elution profile; Chain length distribution

Published in

International Journal of Food Properties
2017, volume: 20, number: 12, pages: 3225-3233
Publisher: TAYLOR & FRANCIS INC

SLU Authors

• Koch, Kristine

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

• Menzel, Carolin

  • Department of Molecular Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Food Science

Publication identifier

• DOI: https://doi.org/10.1080/10942912.2017.1283326

Permanent link to this page (URI)

https://res.slu.se/id/publ/93453