Improvement of in vitro digestibility and thermostability of debranched waxy maize starch by sequential ethanol fractionation

Yao Zhang; Baofang Xing; Degui Kong; Zixuan Gu; Yongjian Yu; Yanjie Zhang; Dandan Li

doi:10.1016/j.ijbiomac.2023.127895

Improvement of in vitro digestibility and thermostability of debranched waxy maize starch by sequential ethanol fractionation

Int J Biol Macromol. 2024 Jan;254(Pt 3):127895. doi: 10.1016/j.ijbiomac.2023.127895. Epub 2023 Nov 4.

Authors

Yao Zhang¹, Baofang Xing², Degui Kong³, Zixuan Gu⁴, Yongjian Yu⁵, Yanjie Zhang⁶, Dandan Li⁷

Affiliations

¹ Postdoctoral Research Program of Materials Science and Engineering, School of Materials Science and Engineering, Jiangsu University of Science and Technology, 212100 Zhenjiang, China; School of Grain Science and Technology, Jiangsu University of Science and Technology, 212100 Zhenjiang, China.
² College of Food Science and Technology, Whole Grain Food Engineering Research Center, Nanjing Agricultural University, 210095 Nanjing, China.
³ Postdoctoral Research Program of Materials Science and Engineering, School of Materials Science and Engineering, Jiangsu University of Science and Technology, 212100 Zhenjiang, China.
⁴ Department of Plant Sciences, North Dakota State University, Fargo, ND 58108, USA.
⁵ School of Grain Science and Technology, Jiangsu University of Science and Technology, 212100 Zhenjiang, China.
⁶ Postdoctoral Research Workstation, Tsui Heung Yuen Healthy Food Co., Ltd, 528437 Zhongshan, China.
⁷ College of Food Science and Technology, Whole Grain Food Engineering Research Center, Nanjing Agricultural University, 210095 Nanjing, China. Electronic address: lidandan@njau.edu.cn.

PMID: 37931861
DOI: 10.1016/j.ijbiomac.2023.127895

Abstract

This study aimed to improve the in vitro digestibility and thermostability of debranched waxy maize starch (DWMS) by sequential fractionation. Waxy maize starch was debranched by pullulanase, followed by sequential precipitation through controlling the ratio of starch supernatants to ethanol at 1:0.5, 1:1, and 1:1.5 (v/v). Subsequently the structural, thermal, in vitro digestive properties of DWMS were investigated. In vitro digestion results showed that the secondary ethanol fractionation of 1:1 on the basis of the initial fractionation (1:0.5) induced a significant higher amount of slowly digestive starch (SDS, 30.0 %) and resistant starch (RS, 58.6 %) amongst all three fractions, along with the highest peak temperature (T_p, 106.4 °C) and the highest decomposition value (T_d, 310.0 °C) in calorimetric (DSC) and thermogravimetry (TGA) measurements. Chain length distribution, surface morphology, and laser confocal micro-Raman spectroscopy (LCM-Raman) analyses revealed that medium (degree of polymerization, DP 13- 36) and long chains (DP ≥37) respectively constituting 72.0 % and 10.2 % of DWMS resulted in the formation of spheroidal crystallites with higher homogeneity and more ordered short-range structures. Overall, this work confirmed that ethanol fractionation is an efficient method for improving the in vitro digestibility and heat stability of waxy maize starch.

Keywords: In vitro digestibility; Sequential ethanol fractionation; Thermostability.

MeSH terms

Amylopectin* / chemistry
Digestion
Hot Temperature
Resistant Starch
Starch / chemistry
Zea mays* / chemistry

Substances

Amylopectin
Starch
Resistant Starch