# Physicochemical and Antioxidant Properties of Selected Polish and Slovak Honeys
## 3 Results and Discussion
### Statistical Discrimination of Honeys
#### 3.2.2 Assessment of OLS Regression Model Fit
After simplification, the model in question took the following form:  
\[\text{Y}=166.9172+8.3961\cdot b^{\star}+11.2498\cdot\text{caffeic acid} \tag{5}\]  
where: Y--total polyphenols content (TPC); \(b^{\star}\)--color change from blueness to yellowish; caffeic acid--content of caffeic acid in honey samples. Assuming a significance level of 5%, the statistically significant variables are \(b^{\star}\), and content of caffeic acids. For every one-unit increase in \(b^{\star}\), the TPC value is expected to increase by approximately 8.4 mg GAE/kg, assuming all other variables remain constant. A one-unit increase in caffeic acid concentration is associated with an increase in TPC of approximately 11.2 mg GAE/kg. The regression model demonstrates a strong fit, with an adjusted R\({}^{2}\) value of 0.918, indicating that 91.8% of the variation in the dependent variable is explained by the independent variables, even after adjusting for model complexity. Among all models discussed the one with the highest coefficient of determination (adjusted R\({}^{2}\) = 0.926) is that describing the relationship between DPPH\({}^{\star}\) free radical scavenging activity and total polyphenol content (DPPPH\({}^{\star}\), Equation (4)). This model includes two colour parameters (\(a^{\star}\), \(b^{\star}\)), and it is important to note that the color of honey is largely influenced by plant-derived components such as polyphenols, carotenoids, flavonoids, and mineral salts [6; 23]. Indeed, all of the \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Variable** & **Coefficient** & **Standard Error** & **t-Statistic** & \(p\)**-Value** & **95\% Confidence Interval** \\ \hline const & 166.9172 & 16.3000 & 10.2400 & 0.0000 & 133.8260 & 200.0080 \\ \(b^{\star}\) & 8.3961 & 0.4150 & 20.2190 & 0.0000 & 7.5530 & 9.2390 \\ caffeic acid & 11.2498 & 5.3470 & 2.1040 & 0.0430 & 0.3940 & 22.1050 \\ \hline \end{tabular}
\end{table} 
Table 4: Parameters of the simplified TPC model as a function of selected variables. \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Variable** & **Coefficient** & **Standard Error** & **t-Statistic** & \(p\)**-Value** & **95\% Confidence Interval** \\ \hline const & 0.1590 & 0.0220 & 7.2400 & 0.0000 & 0.1140 & 0.2040 \\ \(BI\) & 0.0163 & 0.0010 & 21.5180 & 0.0000 & 0.0150 & 0.0180 \\ \hline \end{tabular}
\end{table} 
Table 3: Parameters of the simplified DPPH\({}^{\star}\) free radical scavenging model as a function of selected variables. other models also included variables related to honey color, underscoring the significance of the relationship between color and antioxidant properties of honey. The results of regression analyses are consistent with previous studies that have shown a strong relationship between honey color and its antioxidant activity. Darker honeys, such as honeydew, are usually characterized by a higher content of polyphenols and a greater ability to neutralize free radicals [6; 37]. Color, measured by the parameters \(a^{\star}\), \(b^{\star}\), and \(BI\), can therefore act as a simple indicator of the health-promoting quality of honey [23]. Interestingly, some of the regression models revealed a negative correlation between the content of specific polyphenols and the antioxidant potentials of honey samples determined by spectrophotometric methods. Honey is a complex food matrix in which various constituents, including mineral salts and enzymes, can interact. In such cases, some components, e.g., polyphenols, may exhibit pro-oxidant activity [3]. It should also be noted that individual components of the food matrix exhibit varying affinities for different antioxidant assays [38]. Furthermore, the limitations of the analytical methods used to assess antioxidant potential must be considered. For example, the TPC determination method with the Folin-Ciocalteu reagent is not specific only for polyphenols, and many compounds, including mineral salts, enter into the reaction with this reagent [31].