Extraction of walnut protein using deep eutectic solvent aqueous two-phase system: Investigation of structural and functional properties

Walnut protein (WP) exhibits high nutritional value and excellent techno-functional properties, making it a promising candidate for broad applications in the food industry. It is commonly extracted from the meal after oil processing of walnut through alkali extraction with isoelectric precipitation...

Full description

Saved in:
Bibliographic Details
Main Authors: Yun-Kun Zhu, Mei-Hui Li, Min Yang, Jiang-Xia Xu, Meng-Yao Ren, Zhong-Kai Zhao, Liang Wang, Jie Yang, Jun Liu, Min-Wei Zhang
Format: Article
Language:English
Published: Elsevier 2025-05-01
Series:Food Chemistry: X
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2590157525003931
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Walnut protein (WP) exhibits high nutritional value and excellent techno-functional properties, making it a promising candidate for broad applications in the food industry. It is commonly extracted from the meal after oil processing of walnut through alkali extraction with isoelectric precipitation (AE-IP). In this study, an aqueous two-phase system (DES-ATPS) consisting of betaine-urea/K2HPO4 was used for the extraction of WP from walnut kernels and cold-pressed walnut meal. Comparison with AE-IP, WP extracted through DES-ATPS exhibited enhanced color characteristics and there was no significant difference in protein subunit composition. The WP extracted by DES-ATPS displayed lower Surface hydrophobicity (H0) and intrinsic fluorescence intensities. Conversely, the exposure of internal groups in WP extracted by AE-IP resulted in a higher Zeta potential and a decrease in protein particle size. The comparative analysis revealed fundamentally distinct structural impacts between the two extraction methodologies. Notably, DES-ATPS-isolated WP demonstrated superior solubility under acidic conditions (pH 2).
ISSN:2590-1575