## 3 Results and Discussion
\begin{table}
\begin{tabular}{l c c c c c} \hline \hline \multirow{2}{*}{**Temp (\({}^{\circ}\)C)**} & \multirow{2}{*}{**Time (min)**} & \multicolumn{4}{c}{**Solvents**} \\ \cline{3-6}  & & **Water** & **Methanol** & **Ethanol** & **Acetone** \\ \cline{3-6}  & & & **TPC (mg GAE/g of Freeze-Dried Rose Fruits Pomace)** & & \\ \hline
25 \({}^{\circ}\)C & 15 & 9.85 \(\pm\) 0.40 \({}^{\rm Aa}\) & 16.83 \(\pm\) 0.18 \({}^{\rm Bb}\) & 26.98 \(\pm\) 0.39 \({}^{\rm Bc}\) & 12.93 \(\pm\) 0.22 \({}^{\rm Bc}\)b \\
25 \({}^{\circ}\)C & 30 & 17.08 \(\pm\) 0.62 \({}^{\rm Cb}\) & 17.13 \(\pm\) 0.13 \({}^{\rm Bb}\) & 30.40 \(\pm\) 0.41 \({}^{\rm Bc}\) & 12.70 \(\pm\) 0.51 \({}^{\rm Bc}\)a \\
25 \({}^{\circ}\)C & 45 & 11.70 \(\pm\) 0.72 \({}^{\rm Ba}\) & 15.35 \(\pm\) 0.62 \({}^{\rm Bb}\) & 28.39 \(\pm\) 0.24 \({}^{\rm Bc}\) & 12.40 \(\pm\) 0.33 \({}^{\rm Ba}\) \\
25 \({}^{\circ}\)C & 60 & 12.77 \(\pm\) 0.69 \({}^{\rm Ba}\) & 17.47 \(\pm\) 0.75 \({}^{\rm Bb}\) & 30.78 \(\pm\) 0.27 \({}^{\rm Bc}\) & 11.82 \(\pm\) 0.29 \({}^{\rm Ba}\) \\
45 \({}^{\circ}\)C & 15 & 11.95 \(\pm\) 0.71 \({}^{\rm Ba}\) & 15.94 \(\pm\) 0.72 \({}^{\rm Bc}\) & 31.10 \(\pm\) 1.12 \({}^{\rm Bc}\) & 9.88 \(\pm\) 0.52 \({}^{\rm Aa}\) \\
45 \({}^{\circ}\)C & 30 & 14.63 \(\pm\) 0.08 \({}^{\rm Bb}\) & 17.92 \(\pm\) 0.66 \({}^{\rm Bc}\) & 34.18 \(\pm\) 0.35 \({}^{\rm Cd}\) & 10.58 \(\pm\) 0.42 \({}^{\rm Ba}\) \\
45 \({}^{\circ}\)C & 45 & 13.62 \(\pm\) 0.13 \({}^{\rm Ca}\) & 15.78 \(\pm\) 0.58 \({}^{\rm Bb}\) & 33.49 \(\pm\) 0.24 \({}^{\rm Ce}\) & 15.51 \(\pm\) 0.41 \({}^{\rm Cb}\) \\
45 \({}^{\circ}\)C & 60 & 15.75 \(\pm\) 0.15 \({}^{\rm Ca}\) & 18.17 \(\pm\) 0.99 \({}^{\rm Bc}\)a & 35.56 \(\pm\) 0.48 \({}^{\rm Db}\) & 15.33 \(\pm\) 0.30 \({}^{\rm Ca}\) \\
65 \({}^{\circ}\)C & 15 & 21.36 \(\pm\) 0.26 \({}^{\rm Db}\) & 17.59 \(\pm\) 0.61 \({}^{\rm Ba}\) & 36.27 \(\pm\) 0.26 \({}^{\rm Dc}\) & 14.75 \(\pm\) 0.69 \({}^{\rm Ca}\) \\
65 \({}^{\circ}\)C & 30 & 20.84 \(\pm\) 0.26 \({}^{\rm Db}\) & 17.17 \(\pm\) 0.59 \({}^{\rm Ba}\) & 33.55 \(\pm\) 0.51 \({}^{\rm Cc}\) & 15.42 \(\pm\) 0.31 \({}^{\rm Ca}\) \\
65 \({}^{\circ}\)C & 45 & 25.94 \(\pm\) 0.25 \({}^{\rm Dc}\) & 19.97 \(\pm\) 0.79 \({}^{\rm Cb}\) & 33.80 \(\pm\) 0.37 \({}^{\rm Cd}\) & 14.86 \(\pm\) 0.72 \({}^{\rm Ca}\) \\
65 \({}^{\circ}\)C & 60 & 23.26 \(\pm\) 0.55 \({}^{\rm Db}\) & 18.90 \(\pm\) 0.47 \({}^{\rm Ca}\) & 33.09 \(\pm\) 0.46 \({}^{\rm Cc}\) & 20.36 \(\pm\) 0.48 \({}^{\rm Da}\) \\ Reference sample & 9.34 \(\pm\) 0.66 \({}^{\rm Aa}\) & 7.94 \(\pm\) 0.19 \({}^{\rm Aa}\) & 12.09 \(\pm\) 0.26 \({}^{\rm Ab}\) & 8.16 \(\pm\) 0.61 \({}^{\rm Aa}\) \\ \hline \hline \end{tabular} Data are expressed as the average value over three replications \(\pm\) standard deviation. ANOVA to compare data; different lowercase letters in a row indicate a significant difference between solvents at one specific temperature and time, and different capital letters in a column indicate a significant difference between one solvent in a combination of time and temperature (Tukey’s test, \(p\) < 0.05). Abbreviations: TPC, total phenolic compounds; GAE, gallic acid equivalents.  
\end{table} 
Table 1: Content of total phenolic compounds (TPC) in freeze-dried rose fruits pomace after extraction with various solvents (water, methanol, and ethanol) at 25 \({}^{\circ}\)C, 45 \({}^{\circ}\)C, and 65 \({}^{\circ}\)C for 60 min. In the tests conducted, the lowest TPC recovery was achieved when using single solvents--acetone and water. By using organic solvents in combination with water, TPC recovery was significantly improved. For example, at temperatures of 25 \({}^{\circ}\)C, 45 \({}^{\circ}\)C, and 65 \({}^{\circ}\)C, fifty percent aqueous methanol provided the highest recovery, about 150% higher than that of methanol. A rapid increase in polyphenol content was observed in the first 15 min of extraction for each temperature and solvent used. After 30 min of heating, relative stabilization occurred.