TDNMR characterization of a model crystallizing surfactant system

► Demonstration of TDNMR method as characterization of a crystallizing surfactant-fatty acid formulation. ► Crystallization during cooling for sufficient palmitic acid content (>11wt%). ► Mixed mechanism of crystal growth control via diffusion and surface incorporation. ► Immobile surfactant and water with palmitic acid crystals. ► 2 mass% solubility of palmitic acid in the surfactant solution.