PURPOSE: To test properly the freshness of pickles by preparing a titration curve through titration of the pickle liquid with an alkali solution, and determining the alkali solution titrating quantity in a specified pH range from this titration curve prepared.

CONSTITUTION: To test the freshness of pickles, the pickle liquid is used as specimen, or otherwise is used the filtrated liquid from slurry of pickles formed by a mixer. This is titrated with an alkali solution, and the relation between the titrating quantity and the pH of the specimen is plotted to prepare a titration curve. Using this curve the alkali titration quantity in a specified range is determined, and in accordance with the magnitude of this quantity the freshness of the pickles can be proved if they are acceptable.