Structure and digestibility of crystalline short-chain amylose from debranched waxy wheat, waxy maize, and waxy potato starches

• Published in: Carbohydrate polymers 2010-03, Vol.79 (4), p.1117-1123
• Main Authors: Cai, Liming, Shi, Yong-Cheng
• Format: Article
• Language: English
• Subjects: Applied sciences; Biological and medical sciences; Crystalline structure; Digestibility; Exact sciences and technology; Food industries; Fundamental and applied biological sciences. Psychology; Natural polymers; Physicochemistry of polymers; Resistant starch; Short-chain amylose; Starch and polysaccharides; Starch and starchy product industries; Waxy starch
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2009.10.057

The structure and digestibility of crystalline short-chain amylose (CSCA) from debranched waxy wheat, waxy maize, and waxy potato starches were investigated and compared. The starches (5%, w/w) were cooked in acetate buffer (pH 4.0) and debranched by isoamylase at 50 °C. After 24 h, the mixture was cooled and held at 25 °C for another 24 h. Debranched waxy potato starch had a longer average chain length than debranched waxy wheat and waxy maize starches, resulting in a higher yield of crystallized product. All CSCA products displayed a B-type X-ray diffraction pattern, indicating that low solids concentration (5%) favored the formation of B-type crystals. CSCA from debranched waxy potato starch had a higher peak melting temperature (116.2 °C) and higher resistant starch content (77.8%) than that from debranched waxy wheat and waxy maize starches, suggesting that waxy potato starch is a preferred starting material to prepare products with high resistant starch content by debranching and crystallization.