Embodiments of the process for isolating proteins from a defatted meal comprise extracting the defatted meal with an acidic solvent at a pH of between 2 and 6 to obtain a mixture of treated meal and a first solution of proteins. The process further comprises extracting the treated meal with an alkaline solvent at a pH of between 9 and 12.5 to obtain a mixture of meal residue and a second solution of proteins. The meal residue is separated from the second solution of proteins, and the proteins are separated from the second solution of proteins to obtain one or more protein products.