Abstract: Oppositely charged polymers can undergo associative phase separation, leading to a liquid–liquid-rich phase (coacervates) or a liquid–solid-rich phase (precipitates). Novel properties of the resulting complex arise from the range of biodegradable polymers available, the variety of structures formed, and the tunability of such interactions. The polymer-rich phase can be rearranged around droplets of active compounds or architected in advanced self-assembled structures such as micelles and vesicles, which have increasingly become more similar to biological structures. Polymer association, despite the crucial role of hydrophilic–hydrophobic interactions, is mainly electrostatically driven, and the possibility to control its disassembly inspired the design of several stimuli-responsive particles, mainly for uses in the medical or material fields. The recent progress in the application of such structures renders this topic into an emerging field for new developments in food science Ver menos