All-natural protein-polysaccharide conjugates with bead-on-a-string nanostructures as stabilizers of high internal phase emulsions for 3D printing

The combination of proteins and polysaccharides creates an exceptional platform for stabilizing biphasic systems such as oil in water emulsions. In this paper, we propose the use of natural protein-polysaccharide conjugates (PPCs) extracted from shiitake mushroom roots to stabilize high internal phase emulsions (HIPEs). The PPCs had bead-on-a-string nanostructures with bead (300 nm in diameter) and string (50 nm in thickness) structures corresponding to proteins and polysaccharides, respectively. Having spaced compartments with favourable amphiphilic properties, the PPCs had a three-phase contact angle close to 90°, which were harnessed for the preparation of HIPEs with excellent long-term storage stability (30 d) and heat tolerance (90 °C). The HIPEs were amenable to three-dimensional printing, yielding different objects with strong self-standing and high structural resolution properties. This paper presents a good example of how these unique PPC structures can provide biphasic stabilization, HIPE preparation, and potential applications in food products.