Fabrication and characterisation of soy protein isolate-grafted dextran biopolymer: A novel ingredient in spray-dried soy beverage formulation

Sareh Boostani; Mahmoud Aminlari; Marzieh Moosavi-Nasab; Mehrdad Niakosari; Gholamreza Mesbahi

doi:10.1016/j.ijbiomac.2017.04.019

Fabrication and characterisation of soy protein isolate-grafted dextran biopolymer: A novel ingredient in spray-dried soy beverage formulation

Int J Biol Macromol. 2017 Sep:102:297-307. doi: 10.1016/j.ijbiomac.2017.04.019. Epub 2017 Apr 7.

Authors

Sareh Boostani¹, Mahmoud Aminlari², Marzieh Moosavi-Nasab³, Mehrdad Niakosari³, Gholamreza Mesbahi³

Affiliations

¹ Department of Food Science and Technology, School of Agriculture, Shiraz University, Shiraz, Iran. Electronic address: boostanisa@shirazu.ac.ir.
² Department of Food Science and Technology, School of Agriculture, Shiraz University, Shiraz, Iran; Department of Food Science and Technology, School of Agriculture and Department of Biochemistry, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.
³ Department of Food Science and Technology, School of Agriculture, Shiraz University, Shiraz, Iran.

PMID: 28392389
DOI: 10.1016/j.ijbiomac.2017.04.019

Abstract

Hybridization of macromolecules via the Maillard grafting reaction can punctuate specific forms of biopolymers, resulting in novel functionalities. The current study aimed at investigating and optimizing the conjugation of dextran-soy protein isolate (SPI), and to assess how Maillard modification can affect the properties of a spray-dried soy beverage. Analyses of SDS-PAGE, Glycation degree, SEM micrographs and FT-IR spectroscopy confirmed that the best condition for glycosylation operated on a pH value of 8.5 at 60°C for 8days. Results of differential scanning calorimetry (DSC) clearly show an increased denaturation temperature of proteins. Solubility, emulsifying properties, water holding capacity and DPPH radical scavenging activity of soy proteins were enhanced by conjugation. Spray-dried conjugated powders exhibited significantly higher values of reconstitution properties (solubility index, wettability and dispersibility), compared to un-conjugated ones, because of increased thermal stability and solubility of proteins via glycation. Altogether, the results suggest that dextran conjugation provides further functional attributes to the SPI and thus could improve the applicability of soy proteins in the food industries.

Keywords: Dextran-conjugation; Functional properties; Maillard reaction; Reconstitution; Soy beverage; Spray dry.

MeSH terms

Antioxidants / chemistry
Dextrans / chemistry*
Models, Molecular
Protein Conformation
Soy Milk / chemistry*
Soybean Proteins / chemistry*
Wettability

Substances

Antioxidants
Dextrans
Soybean Proteins