Complex coacervation of pea protein isolate and alginate polysaccharides

► Optimal pea protein isolate–alginate interactions occur between a 4:1 and 8:1 mixing ratio. ► The addition of alginate to pea protein solutions resulted in a decrease in net neutrality. ► Complexation induces minimal conformational changes to the pea protein’s secondary structure. Complex coacerva...

Full description

Saved in:

Bibliographic Details
Published in:	Food chemistry Vol. 130; no. 3; pp. 710 - 715
Main Authors:	Klemmer, K.J., Waldner, L., Stone, A., Low, N.H., Nickerson, M.T.
Format:	Journal Article
Language:	English
Published:	Kidlington Elsevier Ltd 01-02-2012 Elsevier
Subjects:	Alginate Biological and medical sciences Complex coacervation Food additives Food industries Fruit and vegetable industries Fundamental and applied biological sciences. Psychology General aspects Pea protein Phase separation Raman spectroscopy Zeta potential Alginate Complex coacervation Raman spectroscopy Pea protein Zeta potential Phase separation Vegetables Food additive Alginates Protein isolate Pea Protein Grain legume Gelling agent Raman spectrometry Polysaccharide
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	► Optimal pea protein isolate–alginate interactions occur between a 4:1 and 8:1 mixing ratio. ► The addition of alginate to pea protein solutions resulted in a decrease in net neutrality. ► Complexation induces minimal conformational changes to the pea protein’s secondary structure. Complex coacervation between pea protein isolate (PPI) and alginate (AL) was investigated as a function of pH (1.50–7.00) and mixing ratio (1:1–20:1 PPI:AL) by turbidimetric analysis and electrophoretic mobility during an acid titration. Conformational changes to the secondary structures during coacervation were also studied by Raman spectroscopy. Critical structure-forming events associated with the formation of soluble (pH 5.00) and insoluble (pH 2.98) complexes were found for a 1:1 PPI–AL mixture, with optimal biopolymer interactions occurring at pH 2.10 (pHopt). As mixing ratios increased between 4:1 and 8:1, critical pHs shifted towards higher pH. Maximum coacervate formation at pHopt occurred at a mixing ratio of 4:1. Electrophoretic mobility measurements showed a shift in net neutrality from pH 4.00 in homogenous PPI solutions, to pH 1.55 for the 1:1 mixture. As biopolymer ratios increased towards 8:1 PPI:AL, net neutrality shifted to higher pHs (∼3.80). Raman spectroscopy revealed minimal complexation-induced conformational changes. Findings could aid in the design of pH-sensitive biopolymer carriers for use in functional food and bio-material applications.
ISSN:	0308-8146 1873-7072
DOI:	10.1016/j.foodchem.2011.07.114