The production of zinc l-methionine chelate (Zn­(l-Met)2) by a fed-batch reactive crystallization process was reported with enhanced flowability. Zn­(l-Met)2 chelate was obtained through the injection of an aqueous zinc salt into a high pH solution of aqueous l-Met. The total volume of aqueous zinc salt required to induce Zn­(l-Met)2 precipitation, as a function of injection rate and operating temperature, was determined by the real-time attenuated total reflection Fourier transform infrared spectroscopic analysis of a mixed suspension. The smaller this volume at the metastable limit, the larger chelate particles with a high flowability were found to be obtained. Furthermore, improved Zn­(l-Met)2 recovery was achieved upon careful selection of cation and anion species, which are not involved with Zn­(l-Met)2 precipitation in two reagent solutions, based on the salting effects. Finally, Zn­(l-Met)2 particles with excellent flowability and recovery of higher than 97% were successfully produced with a controlled injection of aqueous zinc salts at 30 °C.