## 3 Results
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Sample** & **TEAC * of TACs** & \multicolumn{3}{c}{**TEAC of TLCs**} & \multicolumn{3}{c}{**TEAC of TLs**} \\ \hline  & min–Max value & Median value & min–Max value & Median value & min–Max value & Median value \\ \hline Apple juice & 1.1–2.6 & 1.9 & 0–6.5 & 0.2 & 0.9–9.1 & 1.1 \\ (mg/100 mL juice) & 0.9–1.7 & 1.2 & 0–0.7 & 0.3 & 1.1–1.6 & 1.4 \\ \hline \hline \end{tabular}  
* TEAC = Trolox equivalent antioxidant capacity.  
\end{table} 
Table 4: Total antioxidant capability of TAC, TLC and TL extracts from apple juice and by-products using the DPPH method. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Sample** & **TCC * of TACs** & \multicolumn{3}{c}{**TCC of TLCs**} & \multicolumn{3}{c}{**TCC of TLs**} \\ \hline  & min–Max value & Median value & min–Max value & Median value & min–Max value & Median value \\ \hline Apple juice & 1.5–2.6 & 2.04 & 5.2–11.2 & 5.2 & 6.7–13.2 & 7.8 \\ (mg/100 mL juice) & 0.73–1.4 & 0.75 & 2.4–2.9 & 2.8 & 3.1–4.4 & 3.5 \\ \hline \hline \end{tabular}  
* TCC = Total Carotenoid Content, expressed as mg of \(\beta\)-Caroten Equivalent (CE)/g DW.  
\end{table} 
Table 3: Total carotenoid content of TAC, TLC and TL extracts from apple juice and by-products. reported, while the antioxidant capacity of the TLs of the apple by-products, via DPPH, was found to be similar to previously reported ones for apple by-products [22]. Furthermore, it was found that the TAC and TLC extracts of the juice were of similar antioxidant capacity, while TAC of apple pomace showed much higher antioxidant activity compared to the corresponding TLC samples in these by-products, indicating that the phenolics and carotenoids partitioned in the apple pomace TAC are more bioactive against oxidative stress than the ones migrated to the TLC extract of this apple by-product, which further suggests that apple pomace is a valuable sustainable source of bioactive amphiphilic antioxidants. The results obtained by the ABTS method are shown in Table 5, expressed as ABTS values (umol of Trolox equivalent per g of dry weight of extract; umol TE/g of DW) for each extract. By this assay, it was found that apple juice TACs, TLCs and, subsequently, their TLs (118.2, 44.3 and 153.7 mg/100 mL juice, respectively), showed much higher ABTS value than the relevant TAC, TLC and TL extracts of the by-products (20.7, 22.9 and 43.6 mg/100 g by-products, respectively). Within the same source, TACs of apple juice showed similar ABTS values to its TLC extracts, which was also the case for the apple pomace, meaning that both TACs and TLCs showed similar ABTS values in the apple pomace. Differently than what was observed in the DPPH assay, the use of the ABTS methodology in the present study revealed that the ABTS values in all extracts (both in the juice and in the apple pomace) were higher than what was previously observed in the literature for the whole apples from different apple varieties, indicating that these extracts possess a higher antioxidant capacity than those found for apples in other studies [15]. The ABTS and DPPH methods are among the most popular assays of antioxidant activity determination. More specifically, the ABTS assay is based on the generation of a blue/green ABTS\({}^{\bullet+}\) that can be reduced by antioxidants, and is applicable to both hydrophilic and lipophilic antioxidant systems; whereas the DPPH assay is based on the reduction of the purple DPPH\({}^{\bullet}\) to 1,1-diphenyl-2-picryl hydrazine, using thus a radical dissolved in organic media and is, therefore, applicable to more hydrophobic systems. However, when applied to an analysis of agri-food samples, including extracts from agri-food sources, the antioxidant capacity measurements may be different, depending on the assay used. Differences between DPPH and ABTS radical scavenging activities can be ascribed to reaction media. It has been proposed that the ABTS assay may be more useful than the DPPH assay for detecting antioxidant capacity in a variety of foods [23].