AN EXAMINATION OF THE DECOMPOSITION OF DEXTROSE SOLUTION DURING STERILISATION

A method is described for assessing the degree of decomposition of dextrose in solutions by measuring absorptiometrically the blue colour produced by a reaction with Folin‐Ciocalteu reagent. The amount of decomposition depends on the duration and temperature of the sterilisation process, the concentration of dextrose and the presence of added substances. It is minimal at about pH 3. A product other than 5‐hydroxymethylfurfural is formed. Two breakdown products of dextrose, gluconic acid and 5‐hydroxymethyfurfural, also progressively alter in composition when their solutions are autoclaved for increasing periods either separately or as a mixture.