Microbiological quality and inhibitory potential of selected Croatian apiary honeys

The quality of honey is mainly determined by its sensorial, chemical, physical and microbiological properties. The purpose of this research was to evaluate microbiological properties of 72 honey samples and to determine the number and/or presence of aerobic mesophilic and spore-forming bacteria, moulds, yeasts, sulphite-reducing clostridia, bacteria from the Enterobacteriaceae family and Staphylococcus aureus. Microbiological quality of tested samples was considered good and pathogenic bacteria were not present. Inhibitory potential of selected honey samples was also investigated. Among tested honey concentrations (0.1%, 5%, 10%, 25%, 50% and 75%), the final concentration of 75% had the highest potential. Honeydew and chestnut honey exhibited the strongest inhibitory effect against tested bacterial species, while the lowest inhibition was exhibited by linden (lime tree) honey. Comparing the samples of the same honey type, considerably different inhibitory activity can be detected. Overall, the most sensitive bacterium to the inhibitory effect of tested honey samples was S. aureus, while the most resistant one was Enterococcus faecalis