PHYSICAL AND CHEMICAL PROPERTIES OF PLANT-BASED PROTEINS: STUDY OF GLUTELIN

Resumo

Proteins are essential macromolecules that perform structural, metabolic, storage, and catalytic functions in cells. The growing global population has intensified the search for sustainable alternatives to animal proteins, highlighting plant proteins as promising candidates. However, their successful application depends strongly on their physicochemical and functional properties, underscoring the need for detailed characterization. Plant proteins are classified according to solubility into albumins, globulins, prolamins, and glutelins, which are soluble in water, saline, alcoholic, and alkaline/acidic solutions, respectively. Among these fractions, glutelins remain comparatively understudied despite their importance as seed storage proteins. This review aimed to compile and critically evaluate current knowledge regarding the physicochemical characteristics of glutelin fractions isolated from plant sources. Glutelins are encoded by multigene families and consist of heterogeneous acidic (30–36 kDa) and basic (19–22 kDa) subunits derived from a 57 kDa precursor typically stored in protein bodies (PB II). Their low water solubility arises from strong hydrophobic interactions and disulfide (SH–SS) linkages. Functional properties such as water absorption, emulsifying capacity, and gel formation are key determinants of texture, structure, and shelf life in food systems. Physical, chemical, and enzymatic modifications have shown promise in improving glutelin solubility, emulsification, and foaming properties.

Keywords: Protein, solubility, nutrition.