Effects of growth temperature on multi-scale structure of root tuber starch in sweet potato. (15th December 2022)

• Record Type: Journal Article
• Authors: Guo, Ke; Lin, Lingshang; Li, Enpeng; Zhong, Yuyue; Petersen, Bent Larsen; Blennow, Andreas; Bian, Xiaofeng; Wei, Cunxu
• Is Part Of: Carbohydrate polymers. Volume 298(2022)
• Publication Date: 2022-12-15
• Subjects: Sweet potato -- Growth temperature -- Starch -- Multi-scale structure -- Biosynthesis; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2022.120136
• Languages: English
• ISSNs: 0144-8617

Abstract

Abstract: Sweet potato was planted at three soil and air temperatures (21, 25 and 28 °C) with the same humidity and light time/intensity. Root tuber starches were isolated, and their multi-scale structures were investigated to reveal the effects of growth temperature on starch properties. Growth temperature did not change the morphology and amylose content of starch, but markedly increased the size of starch from volume-weighted mean diameter 12.2 μm to 17.0 μm. Starch grown at high growth temperature exhibited less A branch-chains and lower branching degree of amylopectin and more B2 and B3+ branch-chains of amylopectin than at low growth temperature. With increasing growth temperature, starch changed from CC -type to CA -type, its relative crystallinity and lamellar peak intensity increased, and the thickness of crystalline and amorphous lamellae did not significantly change. Starch grown at high growth temperature exhibited significantly higher gelatinization temperature than at low growth temperature, but had similar gelatinization enthalpy. Graphical abstract: Unlabelled Image Highlights: Sweet potato grown at high growth temperature (GT) increased granule size of starch. Starches grown at high and low GTs had similar morphology and amylose contents. High GT extended branch-chains of amylopectin and decreased its branching degree. Starch grown at high GT exhibited CA -type allomorph with high relative crystallinity. Starch grown at high GT had higher resistance to gelatinization than at low GT.