Table 2.

The commonly used chemical modification methods of protein and their applications.

Modification methods		Description/Applications	References
Chemical modification	Glycation	Improve protein functionalities, emulsifying ability, solubility of the protein, foaming ability, thermal stability, and flavor profile	(125)
		Reduce beany flavor in some plant-based proteins
		Having strong immunomodulatory properties
	Phosphorylation	Keep nutritive bioavailability	(126)
		Improve solubility, thermal stability, viscosity, viscoelasticity, thermal aggregation functional, foaming, and emulsifying properties
		Increase in-vitro digestibility
	Acylation	Improve solubility, emulsifying, foaming and functional properties, emulsion stability, and water holding capacity	(127)
		Increasing the molecular weight of some proteins and hydrophobicity will led to improvement or enhancement of thermal stability and gelling properties
	Deamidation	Mask the bitterness	(128)
		Improve techno-functionality, solubility, water holding capacity, emulsifying, and foaming properties
		Reduce beany flavor, grittiness, and lumpiness
		Decrease the allergenicity of plant-based proteins
	Cationization	Modify techno-functionality	(129)
		Improve solubility, encapsulating, and emulsifying properties
	pH shifting treatment	Change the structural and functional properties of proteins	(130)
		Improve extensibility and tensile properties of the formed films and also the functionality, such as enhanced solubility, surface hydrophobicity, antioxidant activity, rheological, foaming, and emulsifying ability
		Induce protein reactivity by promoting its unfolding