Effects of treatment methods on the formation of resistant starch in purple sweet potato. (15th January 2022)

• Record Type: Journal Article
• Authors: Sun, Hongrui; Fan, Jieying; Tian, Zhigang; Ma, Linyuan; Meng, Yue; Yang, Zhiqiang; Zeng, Xianpeng; Liu, Xiangying; Kang, Lining; Nan, Xiping
• Is Part Of: Food chemistry. Volume 367(2022)
• Publication Date: 2022-01-15
• Subjects: Purple sweet potato -- Resistant starch -- Autoclaving -- Pullulanase -- Structure characterisation; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2021.130580
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Purple sweet potato resistant starch was prepared by autoclaving, pullulanase or a combination of these two methods. Structure, properties and preparation methods of resistant starch were analyzed. The crystal structure of the three sweet potato resistant starch is the same. Yield & thermal stability of resistant starch from combined treatment the highest. Autoclaving, pullulanase treatment or both physically altered starch structure. Abstract: In order to determine the mechanisms underlying resistant starch formation, three treatments were used to prepare resistant starch from purple sweet potato. The resistant starch yield, amylose content, chain length distribution, thermal properties, and crystal structure were determined, and the results were compared with those of unmodified starch. Autoclaving, pullulanase, and pullulanase-autoclaving treatments significantly increased the resistant starch yield, amylose content, shorter amylopectin branch content, and gelatinisation temperatures of native purple sweet potato starch. Resistant starch prepared via pullulanase-autoclaving combination treatment exhibited the highest gelatinisation enthalpy value and the greatest degree of overall thermal stability. X-ray diffraction patterns and Fourier-transform infrared spectra analysis demonstrated that all three treatments transformed the starch crystalline structure from C-type to B-type, and no new groups were generated during the modification process; all the processes were only physical modifications.