## 3 Results and Discussion
This proves the most effective extraction in the initial stage of heating and stabilization over time, most likely resulting from the complete dissolution of the extractant and the extraction of phenolic compounds. [PERSON] et al. (2019) showed that the extraction time after reaching a relatively constant polyphenol value does not significantly affect the results. Moreover, an increase in the applied temperature (25-45-65 \({}^{\circ}\)C) resulted in an increase in TPC concentration for identical solvent concentrations and time conditions. The use of a higher temperature resulted in an increase in the solubility of the solute and the diffusion coefficient, which resulted in the highest TPC concentration being determined at the highest temperature tested ([PERSON] et al., 2017). However, according to the recommendations of other authors, the temperature range was kept low (maximum 65 \({}^{\circ}\)C) to avoid possible \begin{table}
\begin{tabular}{l c c c c} \hline \hline \multicolumn{1}{c}{\multirow{2}{*}{**Temp (\({}^{\circ}\)C)**}} & \multirow{2}{*}{**Time (min)**} & \multicolumn{2}{c}{**Solvents**} \\ \cline{3-5}  & & **50\% Methanol** & **50\% Ethanol** & **50\% Acetone** \\ \cline{3-5}  & & & **TPC (mg GAE/g of Freeze-Dried Rose Fruits Pomace)** & \\ \hline
25 \({}^{\circ}\)C & 15 & 27.81\(\pm\) 0.34 Ba & 27.26 \(\pm\) 0.25 Ca & 31.63 \(\pm\) 0.66 BB \\
25 \({}^{\circ}\)C & 30 & 28.90 \(\pm\) 0.39 BB & 21.55 \(\pm\) 0.44 Ba & 36.79 \(\pm\) 0.60 CC \\
25 \({}^{\circ}\)C & 45 & 27.40 \(\pm\) 0.26 Ba & 22.38 \(\pm\) 0.24 Ba & 36.21 \(\pm\) 0.31 CD \\
25 \({}^{\circ}\)C & 60 & 27.99 \(\pm\) 0.17 Ba & 24.56 \(\pm\) 0.35 Ba & 36.83 \(\pm\) 0.13 CD \\
45 \({}^{\circ}\)C & 15 & 30.70 \(\pm\) 0.23 CD & 26.11 \(\pm\) 0.20 Ba & 31.80 \(\pm\) 0.58 BB \\
45 \({}^{\circ}\)C & 30 & 32.97 \(\pm\) 0.25 CD & 26.51 \(\pm\) 0.42 Ba & 37.35 \(\pm\) 0.45 CD \\
45 \({}^{\circ}\)C & 45 & 31.84 \(\pm\) 0.15 CD & 26.40 \(\pm\) 0.43 Ba & 32.93 \(\pm\) 0.31 BB \\
45 \({}^{\circ}\)C & 60 & 33.89 \(\pm\) 0.51 CD & 28.93 \(\pm\) 0.43 Ba & 34.33 \(\pm\) 0.93 BB \\
65 \({}^{\circ}\)C & 15 & 36.92 \(\pm\) 0.52 CD & 29.57 \(\pm\) 0.19 Ca & 36.05 \(\pm\) 0.57 CD \\
65 \({}^{\circ}\)C & 30 & 29.28 \(\pm\) 0.34 BCa & 30.92 \(\pm\) 0.41 Ca & 34.33 \(\pm\) 0.69 BB \\
65 \({}^{\circ}\)C & 45 & 32.02 \(\pm\) 0.52 Ca & 30.66 \(\pm\) 0.24 Ca & 39.60 \(\pm\) 0.35 DB \\
65 \({}^{\circ}\)C & 60 & 34.65 \(\pm\) 0.34 Ca & 32.90 \(\pm\) 0.12 Ca & 39.12 \(\pm\) 0.62 Da \\ Reference sample & & 7.61 \(\pm\) 0.16 Ba & 10.25 \(\pm\) 0.22 AB & 17.82 \(\pm\) 0.25 Ac \\ \hline \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \\ \end{tabular}
\end{table} 
Table 2: Content of total phenolic compounds (TPC) in freeze-dried rose fruits pomace after extraction with various solvents (50% methanol, 50% ethanol, and 50% acetone) at 25 \({}^{\circ}\)C, 45 \({}^{\circ}\)C, and 65 \({}^{\circ}\)C for 60 min. \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Source** & **Degrees of Freedom** & **Sum of Square** & **Mean Square** & **F-Value** & _p-Value_ \\ \hline Main effects & & & & \\ temperature & 1 & 554 & 554.1 & 243.024 & \(<\)0.0001 \\ time & 4 & 7082 & 1770.5 & 776.535 & \(<\)0.0001 \\ solvent & 6 & 10,178 & 1696.3 & 744.005 & \(<\)0.0001 \\ temperature:time & 4 & 200 & 50.1 & 21.972 & \(<\)0.0001 \\ temperature:solvent & 6 & 163 & 27.2 & 11.915 & \(<\)0.0001 \\ time:solvent & 24 & 1477 & 61.5 & 26.993 & \(<\)0.0001 \\ temperature:time:solvent & 24 & 209 & 8.7 & 3.817 & \(<\)0.0001 \\ Residuals & 140 & 4648 & 33.2 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Multivariate Anova analysis of variance of TPC content on the type of solvent, temperature, and time in freeze-dried rose fruits pomace. degradation of phenolic compounds and denaturation of membranes [41; 42]. Finally, the highest values of TPC were reached at the conditions of 50% acetone and 65 \({}^{\circ}\)C after 45 or 60 min of extraction. The obtained polyphenol contents in the tested extracts are reflected in the studies of other authors.