Comparison of citrus pectin and apple pectin in conjugation with soy protein isolate (SPI) under controlled dry-heating conditions

Xiaobin Ma; Weijun Chen; Tianyi Yan; Danli Wang; Furong Hou; Song Miao; Donghong Liu

doi:10.1016/j.foodchem.2019.125501

Comparison of citrus pectin and apple pectin in conjugation with soy protein isolate (SPI) under controlled dry-heating conditions

Food Chem. 2020 Mar 30:309:125501. doi: 10.1016/j.foodchem.2019.125501. Epub 2019 Sep 7.

Authors

Xiaobin Ma¹, Weijun Chen², Tianyi Yan², Danli Wang², Furong Hou², Song Miao³, Donghong Liu⁴

Affiliations

¹ College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China; Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork, Ireland.
² College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China.
³ Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork, Ireland; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China.
⁴ College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R & D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China; Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China. Electronic address: dhliu@zju.edu.cn.

PMID: 31677451
DOI: 10.1016/j.foodchem.2019.125501

Abstract

In this study, we selected two most commonly-available commercial pectin, i.e. citrus pectin and apple pectin as the grafting polysaccharides to prepare soy protein isolate-pectin conjugates. Despite the similar degrees of methoxylation and acetylation for two pectin samples, apple pectin showed much more complex structures compared to citrus pectin, with a 2.20-fold higher molecular weight and large numbers of side chains. The conjugates were prepared under controlled dry-heating conditions and achieved the degree of graft of 25.00% and 21.85% for citrus and apple pectin, respectively. Formation of the conjugates was further confirmed by SDS-PAGE gel electrophoresis and IR spectra. Attributed to the strong steric-hindrance effect of pectin, the fluorescence intensity and surface hydrophobicity of the soy protein isolate were significantly decreased after Maillard reaction. However, both solubility and emulsifying properties of the conjugates were significantly improved. Results indicated that both pectin samples played favorable roles in protein modification.

Keywords: Conjugate; Emulsifying property; Maillard reaction; Pectin; Solubility; Soy protein isolate; Structure.

Publication types

Comparative Study

MeSH terms

Citrus / chemistry*
Emulsions
Heating
Hydrophobic and Hydrophilic Interactions
Maillard Reaction
Malus / chemistry*
Pectins / chemistry*
Solubility
Soybean Proteins / chemistry*

Substances

Emulsions
Soybean Proteins
citrus pectin
Pectins