Whey Protein–Quercetin–Gellan Gum Complexes Prepared Using pH-Shift Treatment: Structural and Functional Properties

The objectives of this study were to prepare whey protein–quercetin–gellan gum conju- gates using the pH-shift method and to evaluate the impacts of varying pH values and quercetin concentrations on the interaction mechanisms and functional characteristics of the complexes. Spectroscopic analyses (fluorescence, UV-vis, and FT-IR) revealed that new complexes formed under alkaline conditions. Notably, an increasing quercetin concen- tration led to a reduction in complex particle size and an...