Determination of residues of carboxylic acids (mainly galacturonic acid) and their degree of esterification in industrial pectins by colloid titration with Cat-Floc

Abstract

The determination of residues of carboxylic acids (mainly galacturonic acid) in industrial pectins is carried out by colloid titration using a new titrant, Cat-Floc (Poly-NN-dimethyldiallylammonium chloride). The degree of esterification of the methyl ester of galacturonic acid is determined in the same way after hydrolysing the ester with sodium hydroxide in the presence of Cat-Floc. The same samples were analysed by the method of acid-base titration and by colloid titration, and the results obtained are compared and discussed.