Effect of ethanol addition on the physicochemical, structural and in vitro digestive properties of Tartary buckwheat starch-quercetin/rutin complexes

Libo Wang; Yilin Huang; Yanjuan Ren; Haoran Wang; Yue Ding; Guangyue Ren; Tongtong Wang; Zaigui Li; Ju Qiu

doi:10.1016/j.foodchem.2024.139350

Effect of ethanol addition on the physicochemical, structural and in vitro digestive properties of Tartary buckwheat starch-quercetin/rutin complexes

Food Chem. 2024 Apr 15:451:139350. doi: 10.1016/j.foodchem.2024.139350. Online ahead of print.

Authors

Libo Wang¹, Yilin Huang², Yanjuan Ren³, Haoran Wang⁴, Yue Ding³, Guangyue Ren³, Tongtong Wang⁵, Zaigui Li⁶, Ju Qiu⁷

Affiliations

¹ College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China. Electronic address: lbwang0728@haust.edu.cn.
² College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China; School of Food and Strategic Reserves, Henan University of Technology, Zhengzhou, Henan 450001, China.
³ College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China.
⁴ College of Food Science and Engineering, Beijing University of Agriculture, Changping, Beijing 102206, China.
⁵ Institute of Quality Standard and Testing Technology for Agri-Products, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-Food Safety and Quality, Ministry of Agriculture and Rural Affairs, Beijing 100081, China.
⁶ Department of Nutrition and Health, China Agricultural University, No.17 Qinghuadonglu, Haidian, Beijing 100083, China.
⁷ Department of Nutrition and Health, China Agricultural University, No.17 Qinghuadonglu, Haidian, Beijing 100083, China. Electronic address: qiuju@cau.edu.cn.

PMID: 38663246
DOI: 10.1016/j.foodchem.2024.139350

Abstract

The effects of ethanol on the physicochemical, structural and in vitro digestive properties of Tartary buckwheat starch-quercetin/rutin complexes (e-TBSQ and e-TBSR) were investigated. Ethanol restricted the gelatinization of Tartary buckwheat starch (TBS), which resulted an increase in ∆H, G' and G" as well as a decrease in apparent viscosity of e-TBSQ and e-TBSR. The particle size, scanning electron microscopy and X-ray diffraction results showed that ethanol influenced the morphological structure of TBS granules and the starch crystalline structure in e-TBSQ and e-TBSR changed from B-type to V-type when the ethanol concentration was 25%. Saturation transfer difference-nuclear magnetic resonance results revealed that ethanol weakened the binding ability of quercetin/rutin to TBS in e-TBSQ and e-TBSR, leading to a change in the binding site on the quercetin structural unit. The residual ungelatinized TBS granules in e-TBSQ and e-TBSR induced a high slowly digestible starch content, and thus displayed a "resistant-to-digestion".

Keywords: Binding site; Crystalline structure; Ethanol; Phenolics; Slowly digestible starch; Starch morphology.