An objective of this invention is to provide a method for efficiently producing a powdered preservation-improving agent for food with less influence to the quality of taste of food, which have sufficient preservation-improving effect and can suppress bias of acetic acid content resulted from segregation.Provided is a method of powdered preservation-improving agent for food, which is characterized by comprising the following steps: (A) a step of obtaining a mixture by heating an anhydride sodium acetate, an aqueous acetic acid and a sucrose fatty acid ester to 70 to 100℃ while stirring or kneading them； (B) a step of obtaining a solidified object by cooling the mixture obtained in step (A) to 10 to 40℃ while stirring or kneading it； (C) a step of smashing the solidified object obtained in step (B).
