Effect of freeze-drying on interaction and functional properties of pea protein isolate/soy soluble polysaccharides complexes

The objective of this research is to investigate the effect of soluble soybean polysaccharide (SSPS) on properties of pea protein isolate (PPI) with the processing of freeze-drying. First, PPI-SSPS complex was fabricated under the condition of pH 2.5 via electrostatic interaction. Then, PPI-SSPS complex with different mass ratio of PPI and SSPS was processed with freeze-drying. By freeze-drying treatment, the structural part of the PPI particles was unfolded, resulting in improvement of surface hydrophobicity and foamability. Since SSPS adhered to PPI through hydrophobic interaction and hydrogen bonding, the surface hydrophobicity of the reconstituted PPI particles was reduced, meanwhile the emulsion stability was enhanced. The addition of SSPS leaded to rearrange and interconnect of the modified particles, resulting in improvement of interfacial properties and rheological properties. These results indicated that modified PPI-SSPS complex, as compared to the native PPI, exhibited a greater potential to act as a kind of excellent surface-active substance. (C) 2019 Elsevier B.V. All rights reserved.