Process for producing sorbic acid or salts thereof

摘要

A process produces sorbic acid or its salt and includes the step of retaining a slurry or solution containing sorbic acid or its salt while holding an oxygen concentration of a gaseous phase at 4% by volume or less, the gaseous phase being in contact with the slurry or solution containing sorbic acid or its salt. In the process, the oxygen concentration of the gaseous phase may be held at 4% by volume or less while introducing an inert gas into a gaseous phase of a reservoir holding the slurry or solution and/or of a conduit adjacent to the reservoir. Such an inert gases includes, for example, nitrogen gas. The oxygen concentration of the gaseous phase is preferably held at 1% by volume or less. The process can prevent the formation of new color-inducing substances in a purification operation of sorbic acid or its salt, and the obtained sorbic acid or its salt has a minimized degree of coloring and a minimized deterioration of hue over time.