The present invention provides an all-aqueous process and composition for production of silk biomaterials, e.g., fibers, films, foams and mats. In the process, at least one biocompatible polymer, such as poly(ethylene oxide) (PEO) (a well-documented biocompatible material), was blended with the silk protein prior to processing e.g., electrospinning. We discovered that this step avoids problems associated with conformational transitions of fibroin during solubilization and reprocessing from aqueous solution which lead to embrittled materials. Moreover, the process avoids the use of organic solvents that can pose problems when the processed biomaterials are exposed to cells in vitro or in vivo.