## 3 Results
### Characterization of Solid Fractions Obtained after OH and CONV Extraction of Tomato Bagasse
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{2}{c}{**Chemical Composition**} & \multicolumn{2}{c}{**Sample (g/100 g DW)**} \\ \cline{3-4} \multicolumn{2}{c}{**(g/100 g DW)**} & \multicolumn{2}{c}{**SFOH**} & \multicolumn{1}{c}{**SFCONV**} \\ \hline \multirow{6}{*}{Proximate composition} & Ash & 3.32 \(\pm\) 0.21 \({}^{\text{a}}\) & 2.98 \(\pm\) 0.16 \({}^{\text{a}}\) \\  & Protein & 18.72 \(\pm\) 0.47 \({}^{\text{a}}\) & 16.29 \(\pm\) 0.59 \({}^{\text{b}}\) \\  & Total Fatty acids & 21.12 \(\pm\) 0.51 \({}^{\text{a}}\) & 17.82 \(\pm\) 0.3 \({}^{\text{b}}\) \\  & Dietary Fiber & & \\ \cline{3-4}  & & TDF & 62.47 \(\pm\)1.24 \({}^{\text{a}}\) & 59.06 \(\pm\) 0.67 \({}^{\text{b}}\) \\  & & IDF & 50.99 \(\pm\) 0.16 \({}^{\text{a}}\) & 46.01 \(\pm\) 0.13 \({}^{\text{b}}\) \\  & & SDF & 10.86 \(\pm\) 0.85 \({}^{\text{a}}\) & 12.98 \(\pm\) 0.64 \({}^{\text{b}}\) \\ \hline \multirow{6}{*}{Phenolic composition} & Free phenolic extract (FPC) & TPC & 1.46 \(\pm\) 0.05 \({}^{\text{a}}\) & 0.80 \(\pm\) 0.01 \({}^{\text{b}}\) \\  & & ABTS & 0.28 \(\pm\) 0.01 \({}^{\text{b}}\) & 0.99 \(\pm\) 0.15 \({}^{\text{a}}\) \\ \cline{3-4}  & & ORAC & 2.44 \(\pm\) 0.34 \({}^{\text{a}}\) & 1.60 \(\pm\) 0.09 \({}^{\text{b}}\) \\ \cline{1-1}  & & TPC & 0.42 \(\pm\) 0.03 \({}^{\text{b}}\) & 0.73 \(\pm\) 0.12 \({}^{\text{a}}\) \\ \cline{1-1}  & & ABTS & 2.23 \(\pm\) 0.21 \({}^{\text{a}}\) & 2.63 \(\pm\) 0.11 \({}^{\text{a}}\) \\ \cline{1-1}  & & ORAC & 2.41 \(\pm\) 0.22 \({}^{\text{a}}\) & 2.71 \(\pm\) 0.43 \({}^{\text{a}}\) \\ \hline \hline \end{tabular} Values are the mean of three replicates of three independent experiments \(\pm\) standard deviation. TDF, total dietary fiber; IDF, insoluble dietary fiber; SDF, soluble dietary fiber; TPC, total phenolic compounds (g gallic acid eq./100 g DW); ABTS, antioxidant activity by ABTS method (g ascorbic acid eq./100 g DW); GRAC, antioxidant activity (g troloxic eq./100 g DW). Different letters within the same row are statistically significantly different (determined by ANOVA, \(p\) < 0.05).  
\end{table} 
Table 1: The proximate composition, total phenolic compounds, and total antioxidant activity of SFOH and SFCONV (g/100g DW). corn is soaked and cooked in an alkaline solution). The results suggest that OH preserves the compounds (e.g., insoluble fiber), not removing the pericarp and aleurone layer during the process, while insoluble fiber losses in the CONV method could be attributed to pericarp removal during this process, which uses organic solvent. The higher amount of insoluble fiber in SFOH makes OH process an important alternative to produce tomato flours with enhanced bioactive profile, preserving bound phenolics fraction commonly associated with insoluble dietary fiber [35]. Although polyphenols are released toward the liquid extracts, phenolics intimately bound to the fiber (but also to protein and lipids) are not extracted and are part of the flour [36]. Thus, not only free phenolic compounds (FPC) were assessed but also bound phenolics compounds (BPC) of SFOH and SFCONV were analyzed to obtain a more complete phenolic characterization from tomato byproducts after phenolics recovery (Table 1). Significant differences (\(p<0.05\)) between extracted fractions, SFOH, and SFCONV, were found. SFOH exhibited a higher TPC in FPC than in BPC. Additionally, FPC of SFOH contained a higher amount of TPC than SFCONV (\(p<0.05\)). These results could be explained by the extraction solvents used by OH (ethanol-water) and CONV (hexane) extraction. Tomato byproducts are a rich source of liposoluble compounds that are more easily extracted by CONV extraction solvent, which justifies the lower free TPC of SFCONV. The higher TPC richness of free phenolics of SFOH were also reflected in a higher antioxidant activity associated with this flour compared to SFCONV, but only in the ORAC method (\(p<0.05\)). These differences probably arise from different mechanisms to measure the antioxidant capacity of each methodology.