Multiscale non-covalent assembly of proteins and polysaccharides from mechanisms to functional enhancements and applications: A review

In the context of the escalating global emphasis on healthy food and sustainable development, non-covalent assembly systems formed between proteins and polysaccharides have garnered substantial attention. As natural biomolecules, proteins and polysaccharides synergize to form multiscale complexes through mechanisms such as electrostatic interactions, hydrophobic interactions, and hydrogen bonding, thus exhibiting enhanced stability and functionality. This review identifies five major research hotspots in this field using bibliometric analysis, covering complex formation mechanisms, performance enhancement strategies, and application-expansion directions. The key methods for the preparation of protein-polysaccharide complexes are further systematized, followed by an in-depth discussion of the influence of processing parameters, such as pH, ionic strength, and temperature, on the structure and properties of such assembled systems. Based on their intrinsic properties, the essential roles of these complexes in various systems, including emulsions, gels, nanoparticles, and microcapsules, are also presented. Finally, the existing applications of the system in cutting-edge fields such as 3D printing and plant-based meat design are summarized. Despite the excellent biocompatibility, degradability, high nutritional value and low toxicity of these systems, critical challenges, such as ensuring long-term stability, enhancing functionality, and achieving large-scale production remain to be addressed in future research.