A biocomposite powder comprising 20-95% (w/w) chitin-glucan complex (CGC), and up to 50% (w/w) mannose-containing polysaccharides, wherein the biocomposite powder has a bulk density of 0.5 to 1.0 g/cm3, and wherein greater than 60% (w/w) of the particles of the biocomposite powder have a size below 212 μm.