Filtration method for evaluating the salt impurities

Abstract

A procedure for estimation of impurities in the common cooking salt, especially the "refined salt" is presented. The technic is based on the appearence of the filter paper after filtering 10 g of salt in solution through a special filter (Southerland Lacto-Filter ).

Two standardized series of filter paper in decreasing colour scale are presented. The first series deals with different samples of common salt and the second one with "refined salt". It is suggested that a classification of "refined salt" by the filtering test proposed should be established on the basis of the standardized colour scale.