Modifying huauzontle protein by heat, ultrasonication and pH shifting: Evaluation of structural/physicochemical/digestibility properties, and effect on emulsion and foam stability

Abstract

Huauzontle (Chenopodium nuttalliae Saff.) is an underutilized pseudocereal native from Mexico, with high-quality protein content. This work subjected huauzontle protein isolate to ultrasonication, pH-shifting, or heat treatments, evaluating the effect on structural features, emulsifying, and foaming properties. FTIR spectra showed that the intensity of the amide I bands changed significantly, with mainly β-sheet and β-turn structures decreasing, and α-helix structure increasing. The latter structure is associated with increased surface activity and stable interfacial stability. Both, the emulsifying and the foaming properties were enhanced by protein modification. This work confirms that huauzontle protein treated by ultrasonication, pH-shifting, and heat induces changes in the protein's structure and physicochemical properties, contributing to expand its techno-functional applications as in the design of novel foods.