pH-Dependent Changes in the Structural and Functional Properties of Quinoa Protein Isolates in Aqueous Dispersions.
- 1Department of Food Science, Pennsylvania State University, University Park, PA 16802, USA.
- 2Department of Food Science and Technology, The Ohio State University, 2015 Fyffe Road, Columbus, OH 43210, USA.
Abstract
Quinoa protein isolate (QPI) is an emerging plant-based ingredient with high nutritional quality and significant potential for sustainable and clean-label food formulations. However, limited understanding of the relationships among its major protein fractions, physicochemical characteristics, and functionality restricts its broader utilization in food systems. This study investigated the effects of pH conditions (3, 5, 7, 9, and 11) on the particle size distribution, soluble-solid recovery, interfacial properties (surface hydrophobicity, emulsification, and foaming), and albumin-globulin protein fraction profiles of three QPI aqueous dispersions (Q1, Q2, and Q3). Alkaline conditions significantly enhanced QPI soluble-solid recovery (from <20% to >70%) and interfacial functionality, which were associated with the dissociation of large protein aggregates (D₅₀ > 3000 nm) into smaller, well-dispersed particles (D₅₀ < 109 nm) and an increased abundance of soluble albumin-globulin protein fractions, particularly chenopodin. SDS-PAGE, densitometry, principal component analysis, and Pearson correlation supported strong relationships among soluble-solid recovery, particle size reduction, interfacial properties, and soluble albumin-globulin protein fractions. These findings provide an integrated understanding of pH-dependent structure-function relationships of quinoa proteins and demonstrate the potential of pH adjustment for modulating the functionality of QPI aqueous dispersions for sustainable, clean-label ingredients in emulsified foods, aerated systems, and next-generation protein-rich formulations.
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BibTeX
@article{astorgaoquendo2026phdependent,
title = {{pH-Dependent Changes in the Structural and Functional Properties of Quinoa Protein Isolates in Aqueous Dispersions.}},
author = {Liz Astorga-Oquendo and Federico M Harte and Osvaldo H Campanella},
journal = {Foods (Basel, Switzerland)},
year = {2026},
month = sep,
doi = {10.3390/foods15193501},
url = {https://europepmc.org/article/MED/42883608},
note = {CC BY},
}
RIS
TY - JOUR
TI - pH-Dependent Changes in the Structural and Functional Properties of Quinoa Protein Isolates in Aqueous Dispersions.
AU - Liz Astorga-Oquendo
AU - Federico M Harte
AU - Osvaldo H Campanella
PY - 2026
DA - 2026/09/30
JO - Foods (Basel, Switzerland)
DO - 10.3390/foods15193501
UR - https://europepmc.org/article/MED/42883608
AB - Quinoa protein isolate (QPI) is an emerging plant-based ingredient with high nutritional quality and significant potential for sustainable and clean-label food formulations. However, limited understanding of the relationships among its major protein fractions, physicochemical characteristics, and functionality restricts its broader utilization in food systems. This study investigated the effects of pH conditions (3, 5, 7, 9, and 11) on the particle size distribution, soluble-solid recovery, interfacial properties (surface hydrophobicity, emulsification, and foaming), and albumin-globulin protein fraction profiles of three QPI aqueous dispersions (Q1, Q2, and Q3). Alkaline conditions significantly enhanced QPI soluble-solid recovery (from <20% to >70%) and interfacial functionality, which were associated with the dissociation of large protein aggregates (D₅₀ > 3000 nm) into smaller, well-dispersed particles (D₅₀ < 109 nm) and an increased abundance of soluble albumin-globulin protein fractions, particularly chenopodin. SDS-PAGE, densitometry, principal component analysis, and Pearson correlation supported strong relationships among soluble-solid recovery, particle size reduction, interfacial properties, and soluble albumin-globulin protein fractions. These findings provide an integrated understanding of pH-dependent structure-function relationships of quinoa proteins and demonstrate the potential of pH adjustment for modulating the functionality of QPI aqueous dispersions for sustainable, clean-label ingredients in emulsified foods, aerated systems, and next-generation protein-rich formulations.
SN - 2304-8158
ER -