# Physico-Chemical and Melissopalynological Characterization of Czech Honey
## 3 Results and Discussion  
### Physico-Chemical Characterization of Czech Honey  
The results of the physico-chemical analyses of the honeys described in Table 1 are summarized in Table 2. Physico-chemical parameters are important indicators for the classification of honey. The most widely accepted criterion is E. Cond., according to which honeys are divided into honeydew and blossom honeys. The limit value is 80 mS/m (0.8 mS/cm), provided that the F + G sum (sum of glucose and fructose) condition for honeydew is not less than 45 g/100 g and not less than 60 g/100 g for blossom and blend honey [27]. For pharmaceutical honey the maximum limit is 0.8 mS/cm [28; 29]. Based on physico-chemical parameters, the characterization of monofloral honeys is not established legislatively, but is specified in literature sources [7; 8; 9; 14; 19]. Physico-chemical properties mainly reflect the botanical origin, although small differences are also described for different localities. For example, a difference is described in E. Cond. in Greek Thyme honey (0.40 mS/cm) [30] compared to Italian Thyme honey (0.38 mS/cm). For Lime tree, minor differences are reported in E. Cond. as well, namely 0.67 mS/cm in Italy and 0.69 mS/cm in Bulgaria [8; 10]. Physico-chemical parameters can also characterize blend honeys from individual countries, but it is necessary to take into account the great variability. For example, in Portuguese artisanal honey, the average conductivity was 0.6 mS/cm (min./max. ; 0.5-0.9 mS/cm) compared to Irish honeys, where the average conductivity was 0.3 mS/cm (min./max. ; 0.1-0.5 mS/cm) [21]. For comparison, in Czech FH the average conductivity was 0.4 mS/cm (min./max. ; 0.2-0.8 mS/cm) and in HD it reached 1.1 mS/cm (min./max. ; 0.8-1.6 mS/cm). Within the Czech Republic, statistically significant differences for E. Cond. were demonstrated. BH and FH were statistically significantly different from TH and also from HD (\(p<0.05\)). This finding confirms that honeydew honeys are characterized by higher E. Cond., which also applies to lime honey, which is not a typical blossom honey because honey from plant-sucking insects (Hemiptera), in particular _Eucalyptus tiling_ and _Eulceanium coryli_ (L.) [31], also play a significant role in its composition. A suitable parameter for the classification of honeys is also its colour, especially for monofloral honeys [32]. Our results confirmed the difference between HD and FH, LH, RH, and TH honeys. This finding is consistent with [9] who also confirmed that there was no difference between lime, rapeseed, and acacia honeys (Figure 2). HMF, Diastase, % Water, and F. Ac. are physico-chemical parameters that are greatly affected by the handling of honey [33]. These measured values in our study (Table 2) are influenced by the method of sampling, where the honey was taken directly in the honeycombs and then uniformly processed and stored. HMF content in all Czech honeys was \(<\)5 mg/kg. This is also consistent with a study [9] where it was found that over 70% of the analysed European honeys are below this limit. Differences in the HMF content between Czech honeys have not been demonstrated, as the HMF content is not the nature of a type of honey, but an indicator of processing and storage conditions. HMF is also used as quality indicator for pharmaceutical honey where maximum limit of 80 mg/kg is allowed [28; 29]. The diastase activity in Czech honeys was higher in comparison with one study [32], except for rapeseed honey, for which a lower average value (16 DN) was measured than the value reported in the study (27 DN). It can be assumed that the higher measured values are caused by gentle handling of the honey after extraction, which took place under constant conditions, which is not easy to observe in processing and business practices. A statistically significant difference was demonstrated between RH and FH, PH, HD, and RH honeys (\(p<0.05\)). The different water content in honeys is mainly due to climatic conditions and the time of honeycomb harvesting.