## 3 Results and Discussion
### Principal Component Analysis (PCA)  
The principal component analysis is a statistical procedure that allows for the summarising of a large amount of information into a smaller set of \"summary indicators\" that can be more easily visualised and analysed. Multivariate statistical techniques have already been used to monitor the difference between phenolic content and antiradical activity in many types of products, including medicinal plants [12; 45]. The statistical analyses were carried out separately for each tea because their chemical composition was not the same and a different effect of the additives used on their properties was observed. The chemometric assessment (PCA) was performed to identify similarities and differences between samples of fortified teas within a cultivar, and the results obtained are shown in Figure 4.  
The two-dimensional factor analysis of the white tea samples (Figure 4a) showed that, among the analysed catechins, EC played the greatest role in the health-promoting properties of the enriched white teas. In addition, the analysis of the LC-QTOF-MS results showed that all the additives reduced the content of this compound, which was reflected in the decrease in the antiradical activity of the infusions. On the other hand, EC accounted  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **EC** & **ECG** & **EGC** & **EGCG** & **pH** \\ \hline \multicolumn{6}{c}{White tea} \\ \hline DPPH & 0.6955 * & \(-\)0.3989 & \(-\)0.5448 & \(-\)0.3463 & 0.8107 * \\ ABTS & 0.5421 & \(-\)0.3307 & \(-\)0.4539 & \(-\)0.3556 & 0.6109 \\ FRAP & 0.1675 & \(-\)0.1527 & \(-\)0.0179 & \(-\)0.0696 & 0.2410 \\ TPC & 0.3562 & \(-\)0.3287 & \(-\)0.0880 & \(-\)0.0081 & 0.3782 \\ pH & 0.5443 & \(-\)0.0789 & \(-\)0.8989 * & \(-\)0.7378 * & 1 \\ \hline \multicolumn{6}{c}{Black tea} \\ \hline DPPH & 0.1058 & 0.7125 * & \(-\)0.1356 & \(-\)0.0473 & 0.3212 \\ ABTS & \(-\)0.4827 & 0.4065 & \(-\)0.2107 & \(-\)0.1077 & 0.3693 \\ FRAP & 0.3124 & 0.3794 & \(-\)0.1666 & \(-\)0.0919 & 0.3558 \\ TPC & 0.3213 & 0.6953 * & 0.2221 & 0.3062 & \(-\)0.0199 \\ pH & \(-\)0.5651 & \(-\)0.1452 & \(-\)0.9582 * & \(-\)0.9109 * & 1 \\ \hline \hline \end{tabular}  
* EC—epicatechin; EGC—epicallocatechin gallate; EGCG—epicallocation gallate; TPC—total phenolic content; DPPH, ABTS, FRAP—antioxidant activities;’ significant correlation at \(p<0.05\).  
\end{table}
Table 2: [PERSON]’s correlation coefficients.  
for the largest percentage of the analysed catechins in the white tea; therefore, it may play a greater role in its properties than the other catechins. The statistical analysis was performed based on two main components, where PC 1 and PC 2 explained 47.19% and 27.1% of the total variance, respectively, which gave a total result of 74.29%. The analysis of the results of the black tea samples (Figure 4b) demonstrated a significant effect of ECG on the antiradical properties of these infusions, and the main components in this statistical analysis explained in total 75.37% of the total variance. Similarly, ECG was the most abundant catechin in this tea, which may suggest its significant impact on the analysed properties. The present study showed a large influence of pH on the content of EGC and EGCG (Table 2) and a key impact of the additives used on the reaction of the infusion. The highest acidity was observed in teas with the addition of quince and lemon, and the highest amounts of these compounds were recorded in these variants. Since pH-lowering additives may have a positive effect on the extraction of some catechins, i.e., compounds with strong antioxidant properties, their use may increase the health-promoting properties of the consumed infusions.