An Application of Lead Polarography in the Assay of Organic Acids

A method is outlined for the determination of organic acids by precipitation as lead salts. The results of this method, as applied to pigmented and decolorized fruit juices, are compared to titratable acidity and organic acid analysis obtained via ion exchange column chromatography on the same juices. The results indicate that the values obtained by lead precipitation of organic acids, corrected for precipitation due to the presence of orthophosphate, provides a far more accurate picture for organic acids content than titratable acidity alone and may provide a routine procedure for estimation of total organic acids in fruit and vegetable products.