Evaluation of organic acid, saccharide composition and antioxidant properties of some authentic Turkish honeys

Occurring alongside the main saccharide components, antioxidant compounds in honey play significant roles in human metabolism and nutrition. Six individual organic acids and two saccharides were determined by a simple and rapid capillary electrophoretic technique without any special treatment. Gluconic acid was the predominant organic acid and was detected in all samples. Formic, malic, citric and succinic acids were determined at minor concentrations, while oxalic acid was not detected in any of the samples. Glucose and fructose content was found between 223.50 g-kg^-1 and 422.40 g-kg^-1, and 310.20 g-kg^-1 and 642.20 g-kg ^-1, respectively. The fructose/glucose ratios of the ten honey samples in this study were between 1.18 and 1.75 with an average value of 1.50. Gluconic acid content changed depending on the type of honey between 1.50 g-kg^-1 and 13.8 g-kg^-1 with an average value of 6.24 g-kg^-1, while the other organic acids were at minor concentrations, or were not detected at all. The antioxidant properties of the honey were analysed in terms of total polyphenols, ferric-reducing/antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activities. Among the samples, darker honeys showed higher antioxidant values, related to their total phenolic compound contents.