A process for the solid-phase synthesis of salts of organic acids in a granular, free-flowing, and dust-free form particularly suited for use as animal feed additives. A liquid organic acid is applied to an inert, absorbent carrier. A solid base is then added during stirring. The acid is slowly released from the carrier preventing the fast reactions that lead to the formation of clumps. The exothermic reaction releases heat which assists in reducing the moisture content of the product.