Nikolett Czipa, Anna Novák, Béla Kovács
Keywords: analysis of monofloral honey types, proline content, total phenolic content (TPC), linear discriminant analysis
At the Institute of Food Science of the University of Debrecen, we have been analyzing honey for ten years. In our study, the proline and phenolic compound contents of 70 types of monofloral honey (acacia, linden, rape, sunflower, milkweed, chestnut and forest) were examined. During the study, the answer was sought to the question whether it was possible, based on these two parameters, to differentiate monofloral honey types from each other or, in other words, was there an effect of the botanical origin on the amounts of these two compounds.
With the help of linear discriminant analysis, it was determined that groups of monofloral honey could be clearly differentiated from each other. Differentiation of the two groups was not unambiguous in the case of forest and chestnut honey, so the analysis of a third characteristic could be necessary in the case of these two monofloral honeys.
Honey is a natural, sweet substance, produced by the Apis mellifera bees. In terms of origin, it can come from two sources, from the nectar secreted by the plants (honey of nectar origin), or from the substance secreted by insects, e.g., aphids (honeydew honey). In Hungary, mainly honey of nectar origin is produced, in an amount of roughly 17,000 tons, most of which is exported. With this quantity, in terms of European Union member states, we are ranked third on the list of honey exporters behind Spain and Romania . In Hungary, acacia, linden, sunflower, rape and milkweed honeys are typically consumed, but chestnut, wild tobacco and lavender honeys play significant roles as well.
Honey is a complex food, containing a number of beneficial compounds, helping to preserve human health, and so a significant role is attributed to it not only in the human diet, but also in medicine. Its antibacterial properties are due to its high sugar content, pH and hydrogen peroxide content, among other things . In addition, moderate consumption of honey also provides a protection against gastro-intestinal infections .
Honey composition is largely dependent on the plant it is derived from, and it can also be influenced by soil properties and post-collection treatment . To determine the botanical origin of honeys, the most widely used method is pollen analysis, however, using this method, added pollen grains cannot be differentiated from those of natural origin. Even though type identification of honey is based on the pollen ratio, it has been shown by previous studies that the values of certain physico-chemical parameters are characteristic of different monofloral honeys , . In our research, the answer was sought to the question whether the different monofloral honeys could be differentiated, based on the parameters chosen by us. read more ...