# The Total Phenolic Content and Antioxidant Activity of Nine Monofloral Honey Types
## 3 Results and Discussion
### Determination of Electrical Conductivity and Color  
The different values of electrical conductivity and color are related to the botanical origin of honeys. Honeydew honeys had higher values than blossom honeys, with the chestnut honey showing the highest mean electrical conductivity (1.679 \(\pm\) 0.3 mS/cm), followed by fir (1.407 \(\pm\) 0.18 mS/cm), oak (1.255 \(\pm\) 0.18 mS/cm) and pine (1.170 \(\pm\) 0.12 mS/cm) (Figure 2). Manuka, thyme and citrus honeys showed the lowest mean electrical conductivity (0.538 \(\pm\) 0.07, 0.415 \(\pm\) 0.09 and 0.254 \(\pm\) 0.07 mS/cm, respectively).  
Also, honeydew honeys were generally darker than blossom honeys, with oak honey being the darkest, as they had the lowest average L* parameter (L* = 31.67 \(\pm\) 0.10), followed by chestnut (L* = 33.30 \(\pm\) 0.45) and pine (L* = 33.30 \(\pm\) 0.15), while citrus honey was the lightest (L* = 33.30 \(\pm\) 0.15) (Figure 3).  
Manuka honey, though considered as blossom, was darker (L* = 3.34 \(\pm\) 0.39) than Greek blossom monofloral honeys, and even darker than fir honey (L* = 3.41 \(\pm\) 0.01). Furthermore, erica and manuka honeys had the highest mean redness value (a* = 3.14 \(\pm\) 2.33, 2.79 \(\pm\) 1.69, respectively) and mean yellowness value (b* = 9.59 \(\pm\) 4.09, 9.07 \(\pm\) 2.49, respectively) probably due to the presence of red and yellow components (ex. anthocyanins, flavonoids, carotenoids) in their nectar.  
Electrical conductivity, along with other physicochemical parameters, is important in the characterization of honey. In our study, most blossom honey had electrical conductivity values below 0.8 mS/cm, as specified in the Honey Directive (110/2001, EE), while the mean values for honeydew and chestnut honey were over that limit [42]. However, Jerusalem thorn honey, despite being classified as blossom based on field observations, had an average electrical conductivity higher than 0.8 mS/cm. As a result, this specific type of honey cannot be classified and marketed as blossom honey, even though it exhibits the microscopic and sensory characteristics of such honey. Similar findings have been documented by [PERSON] et al. [43]. Furthermore, 40% of cotton honey samples had electrical conductivity exceeding 0.8 mS/cm, despite exhibiting the characteristics of blossom honey, making their promotion challenging. [PERSON] et al. [44] have suggested to include these monofloral honey types in the exceptions of Honey Directive (110/2001, EU).  
Figure 3: Color parameters L* (10\({}^{-1}\)), a*, b*, of ten monofloral honey types. Note: Different latin letters in each group show statistically significant differences according to [PERSON]’s multiple range test, a = 0.05.  
Figure 2: Electrical conductivity (mS/cm) of ten monofloral honey types. Note: Different latin letters in each group show statistically significant differences according to [PERSON]’s multiple range test, a = 0.05.  
Multiple authors have reported similar average electrical conductivity for the different types of honey they studied [9; 28; 29; 41; 44; 45; 46; 47]. However, [PERSON] et al. [35], [PERSON] [48] and [PERSON] et al. [49] found lower values for chestnut honey (1.13 \(\pm\) 0.25, 1.1 \(\pm\) 0.2, and 1.43 \(\pm\) 0.33 mS/cm, respectively), compared to our findings. Additionally, [PERSON] et al. [31] and [PERSON] et al. [49] noted lower values for oak honey (1.0 \(\pm\) 0.1, 1.13 \(\pm\) 0.31 mS/cm, respectively). Lastly, while [PERSON] et al. reported similar electrical conductivity values for citrus honey [50], [PERSON] et al. (0.616 \(\pm\) 0.019 mS/cm) and [PERSON] et al. (0.40 \(\pm\) 0.20 mS/cm) referred to higher values [51; 52].  
Furthermore, regarding the CIElab parameters, the findings in the existing literature are different regarding the same honey type, compared to this research [9; 53]. These variations could be attributed to the honey's different geographical origins or to the use of different colorimetric methods (such as transmittance or reflectance, and analysis of fluid or crystallized honey) [53].