title: Properties of starch from potatoes differing in glycemic index.
abstract: Potatoes are a popular source of dietary carbohydrate worldwide and are generally considered to be a high glycemic index (GI) food. Potato starch characteristics play a key role in determining their rate of digestion and resulting glycemic response. Starches isolated from seven potato cultivars with different GI values, including a low GI cultivar (Carisma), were examined for relative crystallinity, granule size distribution, amylopectin chain length, and thermal and pasting properties. Starch from the Carisma cultivar was more thermally stable and more resistant to gelatinization, with significantly higher (p < 0.05) pasting temperature and differential scanning calorimetry (DSC) gelatinization onset, peak and conclusion temperatures, compared to the other cultivars. Differences between the potatoes in the other properties measured did not align with the GI ranking. Thermal analysis and starch pasting properties may be useful indicators for preliminary identification of potato cultivars that are digested slowly and have a lower GI.
authors.affiliation: Department of Plant and Food Sciences, Faculty of Agriculture and Environment, The University of Sydney, NSW 2006, Australia. les.copeland@sydney.edu.au.
authors.forename: Kai
authors.initials: K
authors.lastname: Lin Ek
authors.forename: Shujun
authors.initials: S
authors.lastname: Wang
authors.forename: Jennie
authors.initials: J
authors.lastname: Brand-Miller
authors.forename: Les
authors.initials: L
authors.lastname: Copeland
mesh_terms: D000687:Amylopectin / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D055598:Chemical Phenomena; D004040:Dietary Carbohydrates; D004063:Digestion; D038321:Glycemic Index; D006358:Hot Temperature; D010316:Particle Size; D010758:Phosphorus / Q000032:analysis; D011198:Solanum tuberosum / Q000737:chemistry* / Q000145:classification; D013213:Starch / Q000737:chemistry*
chemical_list: D004040:Dietary Carbohydrates; D010758:Phosphorus; D013213:Starch; D000687:Amylopectin