Pattern of pH and electrical conductivity upon honey dilution as a complementary tool for discriminating geographical origin of honeys

Seven physicochemical parameters (water content, ash, water activity, free, lactone and total acidity, pH and electrical conductivity) were analyzed in 19 nectar honeys of different floral origin and from several regions of Argentina. In addition, the pattern of electrical conductivity and pH upon honey dilution were also studied with increasing honey concentration, the pH values decreased exponentially. The dependence of specific electrical conductivity (kappa) on honey concentration was characterized by a maximum at a kappa value (kappa(max)) corresponding to a dry solids of honey concentration of 30-35% (w/w). For a given geographical region, ash and acidity values were useful for discriminating honeys of different floral origins. The most adequate parameters for discriminating honeys of different geographical origin were those which described the patterns of pH and electrical conductivity with changes of honey concentration. (c) 2006 Elsevier Ltd. All rights reserved.