A Picric Acid Method for the Simultaneous Determination of Lactose and Sucrose in Dairy Products

Abstract

A method, based on the reduction of picric acid and utilizing a photoelectric colorimeter, for the simultaneous detn. of lactose and sucrose in dairy products is described. It is empirical but relatively simple and time saving compared with methods of the A.O.A.C. and other recognized procedures. Comparative studies indicate that the method is as accurate as the Munson-Walker, the polarimetric or White''s modification of the Munson-Walker although analysis indicates that the variation of replicates is slightly wider. The method can be applied to either sugar alone as well as to both and is of particular use in the analysis of sweetened condensed milk and ice cream where sucrose substitutes are absent.