The optimization of an organic acid production process downstream of fermentation is presented. Sodium salt solution of the organic acid (Na salt) solution is the product in the industrial fermentation process for the organic acid production and until today, it has not been attempted to directly crystallize/isolate the Na salt under these circumstances. Evaporation crystallization of Na salt directly from the solid-free fermentation broth without purification can be realized with high product purity. Parameters limiting the crystallization/separation process are identified and discussed. The above points are considered as a function of viscosity, crystal size, and product purity. Comparison with the existing process completes this evaluation. The impact on the process design and alternatives are illustrated. The modification of hybrid processes using crystallization also as a purification step is investigated.