Determination of conventional sugars in some Sudanese honey samples

Abstract

The aim of this research was to determine the percentage of conventional sugars (glucose, fructose, sucrose and maltose) in three honey samples collected from South Sudan, Al Fashir and Al Gadarif. The values of refractive index, pH, and water content were also measured. The refractive indexes were 1.490, 1.490 and 1.489 The pH values were 4.26,4.37and 4.32 and the water contents were 18,18.1and 15.4 respectively. The percentage of glucose, fructose, sucrose determined by classical methods (Lane-Eynon and iodometric titration) were 36.2, 37.48 and 2.35 in South Sudan sample ,33.9, 36.5and 3.9 in Al Fashir sample, 40.00, 19. 66 and 11.36 in Al Gadarif sample,respectively The percentage of glucose, fructose, sucrose, and also maltose determined by HPLC were 31.98, 38.41 ,0.423and 1.294 in South Sudan sample; 35.32, 37.41, 0.702and0.790 in Al Fashir sample and 35.80, 33.40, 15.71and 0.0 in Al Gadarif sample respectively. The results obtained by HPLC were usually more accurate, because the technique is more sensitive compared with classical methods. The F/G (fructose/glucose) ratio of the honey of South Sudan and Al Fashir were seemly more genuine than that of of Al Gadarif that might be adulterated with other sweeteners, most likely cane honey or molasses (artificial honey).