Enzymatic cross-linking of pea and whey proteins to enhance emulsifying and encapsulation properties

• Published in: Food and bioproducts processing 2023-05, Vol.139, p.204-215
• Main Authors: Kim, Woojeong, Wang, Yong, Ye, Qianyu, Yao, Yin, Selomulya, Cordelia
• Format: Article
• Language: English
• Subjects: Encapsulation; Enzymatic cross-linking; Pea protein; Protein interaction; Whey protein; β-carotene
• ISSN: 0960-3085
• DOI: 10.1016/j.fbp.2023.03.011

Improving the functionality of commercial plant proteins is essential for food application. Here an alternative strategy is provided to modify the structure of pea protein by microbial transglutaminase-induced cross-linking with whey protein for enhancing emulsifying and encapsulation properties. The protein structures and the physicochemical stability of β-carotene-loaded emulsions were investigated subject to protein ratio and cross-linking. Formation of disulphide and isopeptide bonds between heteroproteins according to cross-linking changed protein structures by exposing the hydrophobic sites of proteins with stiffer network. The cross-linked pea/whey protein complexes at protein ratio of 2:1 formed a stable emulsion with a droplet size of 0.10 µm, showing no phase separation for 30 days of storage and high encapsulation efficiency of 92%. These findings provided a novel strategy to design plant/dairy protein networks to protect lipophilic bioactive compounds by replacing half or more dairy protein with plant protein, leading to gradual change towards plant-based diets. [Display omitted] •Enzymatic cross-linking between pea and whey proteins formed rigid protein network.•Emulsion stability was enhanced by cross-linking with submicron droplets.•Highly stable emulsions were formed by cross-linked pea/whey protein at 2:1 ratio.•Protein cross-linking enhanced encapsulation and protection of β-carotene.