Gum Arabic-Mediated Synthesis of Glyco-pea Protein Hydrolysate via Maillard Reaction Improves Solubility, Flavor Profile, and Functionality of Plant Protein

Abstract

Pea protein hydrolysate (PPH) is successfully conjugated with gum arabic (GA) through Maillard-driven chemistry. The effect of cross-linking conjugation on the structure, solubility, volatile substances, emulsification, and antioxidative activity of glyco-PPH is investigated, and found to improve all properties. The formation of glyco-PPH is confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier-transform infrared (FTIR), and scanning electron microscopy (SEM). Size exclusion chromatography-multi angle light scattering (SEC-MALS) unveils that the maximum molecular mass of glyco-PPH occurs after 1 day of conjugation and approximately 1.2 mol of gum arabic conjugates on one mole of PPH. Headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC–MS) reveals the odor changes of glycoprotein before and after cross-linking. We have also prepared oil-in-water emulsions using glyco-PPH, which have enhanced physical stability against pH changes and chemical stability against lipid oxidation. The mechanism proposed involves Maillard-driven synthesis of the cross-linked PPH-GA conjugates, which increase the surface hydrophilicity and steric hindrance of glyco-PPH. These findings could provide a rational foundation for tailoring the physicochemical properties and functionalities of plant-based protein, which are attractive for food and functional materials applications.

Structural, physicochemical and functional properties of Semen Ziziphi Spinosae protein

“…Owing to the introduction of glycosyl groups, the content of hydroxyl in the molecule of the protein that contains sugar components increases, and the hydrophilicity of the protein is improved. 65 Under the synergistic effects of the above two factors, SZSP can more easily reach a hydrophilic-lipophilic equilibrium state in the dispersion system, signicantly improving the emulsifying ability of SZSP. The EAI of SZSP increased signicantly when the pH was greater than 8, indicating that the protein contains more negative charges, which is more conducive to the formation of stable emulsions.…”

Modification of pulse proteins for improved functionality and flavor profile: A comprehensive review

“…The far‐reaching insights into changes of animal protein functionalities after gaining controlled glycation, such as improved protein solubility, enhanced emulsification activity, upgraded foaming properties, reinforced thermal stability, and advanced antioxidant activity, have shed light on the glycation of pulse proteins. In our very recent series of study, we observed a darker color accompanied by interfacial and morphological microstructure alterations of yellow pea proteins when extending glycation with gum Arabic (Zha, Dong, et al., 2019a, 2019b; Zha, Yang, et al., 2019). In addition, the functionalities of glycated yellow pea protein including solubility, emulsification, and antioxidant activity were improved accordingly.…”

“…We claim that the improvement of pea protein functionality is mainly because of the increased steric hindrance rather than electrostatic repulsion generated by the grafted polysaccharide. The inspiring fact has stimulated us to seek for potential means to improve the number of carbohydrate moieties to be anchored to proteins because the grafting rate is low (Zha, Yang, et al., 2019). The flavor improvement of glycated pulse protein has yet to be broadly investigated.…”

“…The flavor improvement of glycated pulse protein has yet to be broadly investigated. We recently throw light on glycating yellow pea protein with gum Arabic, which not only diminished the relevant off‐flavors but endued with nonspecific aroma flavor attributes for resultant end‐products (Zha, Dong, et al., 2019b; Zha, Yang, et al., 2019). The mitigation of off‐flavors was partly attributed to the disappearance of lipoxygenase after glycation (Zha, Dong, et al., 2019b); and it is also speculated that the structural reorientation and conformational change of pea protein lead to the release of protein‐bonded off‐odors during glycation (Zha, Dong, et al., 2019b; Zha, Yang, et al., 2019).…”

“…Second, the perceived taste or palatability of pulse protein–containing products is not well accepted by the Western palate, with reproaches including bitter taste and green/beany odor (Roland et al., 2017). Particularly, indigenous odorants of pulse proteins arising from oxidative degradation of unsaturated fatty acid in protein‐bound lipids catalyzed by lipoxygenase have proved problematic upon subsequent applications (Rackis et al., 1972, 1979; Sessa & Rackis, 1977; Zha, Yang, et al., 2019). Third, the presence of certain protein and nonprotein antinutritional compounds, including lectins (carbohydrate‐binding protein), trypsin/chymotrypsin inhibitors (protein), and flatulence factors (raffinose oligosaccharides), can deteriorate human physiological functions such as hemagglutination, bloating, vomiting, and pancreatic enlargement (Roy et al., 2010).…”