Abstract: An improved vegetable protein adhesive binder which can be used in paper coating compositions at much lower levels than conventional vegetable protein adhesive binders while imparting to the paper coating composition rheological and other properties equivalent to conventional paper coating compositions containing higher levels of vegetable protein adhesive binders is prepared by forming an alkaline dispersion of a vegetable protein material and a polyacrylate, mixing the polyacrylate and the vegetable protein material at a temperature and for a time sufficient to achieve entanglement of the polyacrylate with the vegetable protein material, and co-precipitating the vegetable protein material and polyacrylate at the isoelectric point of the vegetable protein.