## 3 Results and Discussion
### Trolox Equivalent Antioxidant Capacity (TEAC)  
The TEAC assay is another widely used method for assessing the antioxidant capacities using free radicals. This assay determines the ability of an antioxidant to scavenge the ABTS (2,2'-azino-bis(3-ethylbenzothazoline-6-sulfonic acid) radical, a blue-green chromophore [52]. In this study, the roasting degree did not significantly affect the TEAC in \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Variables** & **Extraction** & **Light-Medium** & **Medium** & **Moderately Dark** & **Very Dark** \\ \hline DPPH\(\bullet\) scavenging & Espresso & 10.20 \(\pm\) 0.34 \({}^{\text{a}}\) & 8.85 \(\pm\) 0.60 \({}^{\text{b}}\) & 8.13 \(\pm\) 0.23 \({}^{\text{b}}\) & 8.33 \(\pm\) 0.40 \({}^{\text{b}}\) \\ activity (mg AAE/mL) & Drip & 2.55 \(\pm\) 0.01 \({}^{\text{a}}\) & 2.44 \(\pm\) 0.07 \({}^{\text{ab}}\) & 2.17 \(\pm\) 0.14 \({}^{\text{b}}\) & 2.20 \(\pm\) 0.26 \({}^{\text{b}}\) \\ \hline FRAP (\(\mu\)mol & Espresso & 107.56 \(\pm\) 6.20 \({}^{\text{a}}\) & 96.81 \(\pm\) 8.65 \({}^{\text{a}}\) & 98.12 \(\pm\) 1.83 \({}^{\text{a}}\) & 77.02 \(\pm\) 6.21 \({}^{\text{b}}\) \\ FeSO\({}_{4}\)/mL) & Drip & 26.56 \(\pm\) 1.12 \({}^{\text{a}}\) & 24.18 \(\pm\) 2.50 \({}^{\text{a}}\) & 23.61 \(\pm\) 1.74 \({}^{\text{a}}\) & 17.41 \(\pm\) 0.45 \({}^{\text{b}}\) \\ \hline TEAC (mg TE/mL) & Espresso & 66.86 \(\pm\) 0.69 \({}^{\text{ns}}\) & 62.36 \(\pm\) 2.27 \({}^{\text{ns}}\) & 63.47 \(\pm\) 2.42 \({}^{\text{ns}}\) & 63.68 \(\pm\) 3.66 \({}^{\text{ns}}\) \\  & Drip & 13.47 \(\pm\) 2.20 \({}^{\text{ns}}\) & 14.08 \(\pm\) 0.17 \({}^{\text{ns}}\) & 13.98 \(\pm\) 0.65 \({}^{\text{ns}}\) & 13.11 \(\pm\) 1.20 \({}^{\text{ns}}\) \\ \hline \hline \end{tabular}  
* Data are expressed as mean \(\pm\) standard deviation (\(n\) = 3). Means with different letters (a,b) in the same row denote significant differences according to the one-way analysis of variance (ANOVA) and [PERSON]’s multiple comparison test (\(p\) < 0.05). ns, not significant.  
\end{table} 
Table 5: TEAC, DPPH radical scavenging activity, FRAP of coffee extracts. both the espresso and drip coffee extracts, unlike the FRAP and DPPH radical scavenging activity. In the espresso, the value of the TEAC at the Light-medium was slightly higher compared to the Medium, Moderately dark, and Very dark roasting, but there were no significant differences among the samples. In the case of drip coffee, TEAC slightly increased in Medium than in Light-Medium but showed a tendency to decrease as the degree of roasting increased. However, there were also no statistical differences among groups. In another study regarding hot water extract of _Colombian arabica_ coffee beans, extracts with the light and medium roasted coffee beans had higher TEAC compared to the green bean extract, whereas the dark roasted coffee bean extract did not; however, the TEAC between light roasting and medium roasting did not significantly differ [53]. In the TEAC assay, the measurements are usually based on a fixed time (4-6 min) [21], which cannot consider antioxidants' different kinetic characteristics. It has been reported that several polyphenols, including ferulic acid, resveratrol, and others, did not complete their reaction at a fixed time [54]. A study by [PERSON] et al. also has reported that the antioxidants show a different reactivity towards ABTS and DPPH radicals. The caffeic acid, with a methoxy group, showed a higher antioxidant capacity with ABTS radicals than with DPPH radicals. In contrast, ferulic acid, which possesses a hydroxyl instead of the methoxy group, was a better antioxidant component with DPPH radicals than ABTS radicals. Therefore, TEAC did not decrease as the roasting proceeded, unlike the DPPH radical scavenging activity results, which might be because antioxidants with a methoxy group, showing higher antioxidant capacity with ABTS radicals, might not be significantly affected by roasting.