Spectrophotometric Determination of Sorbic Acid in Apple Cider^a

Abstract

An improved method for measuring sorbic acid in cider is based on dilution of the sample and direct ultraviolet readings at 262 m.~. This method was compared with the distillation method for sorbic acid usually applied to cider. The latter method produced ultraviolet-absorbant materials that interfered with sorbic acid determinations and were shown to he affected by the sugar content of the cider and the distillation techniques.The ultraviolet-interfering materials in cider distillates have absorption peaks and chemical properties similar to those of 5-hydroxymethylfurfural.