Thermoplastic protein produced from bloodmeal (BM) becomes brittle as moisture desorbs from the material. Tensile tests, DMA, DSC and WAXS are used to determine the effect of replacing water with TEG. Specimens containing 0–30 pphBM TEG and combined water and TEG content prior to extrusion of 60 pphBM are extruded, injection-moulded and conditioned. TEG increases the strain at break while reducing strength. 20 pphBM is chosen as an appropriate compromise between strength and ductility with a tensile strength of 6 MPa, a Young's modulus of 250 MPa, a toughness of 2.8 MPa and a strain at break of 0.53. When TEG is held at 20 pphBM and the amounts of other additives varied urea has the largest effect on conditioned properties, showing that H-bonding still dominates protein/protein interactions.