## 3 Results and Discussion
### Aroma Profiling
\begin{table}
\begin{tabular}{c c c c c c} \hline
**COMPOUNDS** & **RT** & **CTR** & **CV** & **CO** & **HD** \\ \hline
**HYDROCARBONS** & & & & & \\
**(7)** & & & & & \\
1.3-cyclopentadiene. & & & & & \\
5.5-dimethyl-2-ethyl- & & & & & \\
1.4-cyclohexadiene. & & & & & \\
3-ethenyl-1.2-dimethyl- & & & & & \\ naphthalene. & & & & & \\
2-methyl- & & & & & \\ cyclododecane & 25.48 & nd & x & x & x \\ nonane & 30.93 & x & x & x & x \\
1-octadecyne & 34.95 & nd & x & x & x \\ trans-1.2- & & & & & \\ diphenylcyclobutane & & & & & \\
**PYRAZINE (2)** & & & & & \\ pyrazine. & & & & & \\
2-methoxy-3- & & & & & \\ (1-methylpropyl) & 17.92 & x & x & x & x \\ (2-sec-butyl-3- & & & & & \\ methoxypyrazine) & & & & & \\ pyrazine. & & & & & \\
2-methoxy-3- & & & & & \\ (2-methylpropyl) & 18.21 & x & x & x & x \\ (2-isobutyl-3- & & & & & \\ methoxyrazine) & & & & & \\
**TERPENS (17)** & & & & & \\ citronell & 12.41 & x & nd & x & x \\ \(\beta\)-ccime & 12.75 & x & x & x & x \\
3-Carene & 13.18 & x & x & x & x \\ p-cymene & 14.39 & x & x & x & x \\ carvacrol & 15.08 & x & x & x & x \\ (+)-4-carene & 15.19 & nd & x & x & x \\ cosmee & 15.85 & x & x & x & x \\ trans caren 3-ol & 16.31 & x & x & x & x \\ neo-allo pichene & 16.75 & x & x & x & x \\ \(\beta\)-ciclocitral & 19.65 & x & nd & x & x \\ perillol & 20.66 & x & x & nd & x \\ cis-verbenol & 21.46 & x & nd & nd & x \\ thymol & 21.69 & x & x & x & x \\ (-)-myrtenol & 22.82 & x & x & x & x \\ geranil linalol & 28.99 & x & x & x & x \\ gerani & 30.66 & x & x & nd & x \\ trans geranil & & & & & \\ geraniolo & & & & & \\
**SESQUI** & & & & & \\
**TERPENES (19)** & & & & & \\ (E)2, (Z)4, & & & & & \\ (E)6-allofarmesene & 20.41 & x & x & x & x \\ \(\alpha\)-copaene & 24.96 & x & x & x & x \\ \(\beta\)-panasinsene & 25.43 & x & nd & nd & x \\ \(\alpha\)-lopipinene & 26.23 & x & x & x & x \\ \(\alpha\)-santalene & 26.38 & x & x & x & x \\ \(\beta\)-curcumene & 26.88 & x & x & x & x \\ carvophyllene & 27.17 & x & x & nd & nd \\ ylangene & 27.23 & x & x & x & x \\ \(\beta\)-copaene & 27.55 & x & x & x & x \\ santene & 27.64 & x & x & x & x \\ di-epi-\(\alpha\)-cedrene & 27.83 & nd & x & nd & nd \\ \hline \end{tabular}
\end{table} 
Table 4: _Cont._The results are consistent with the type of compost used. In fact, CO obtained from olive pomace was less rich in macronutrients than CV. In CTR, a greater presence of aldehydes emerged, while in HD, a chemical class of compounds did not prevail, rather, a similar and decreasing tendency among terpen, esters, aldehydes, and finally, alcohols was observed. Among terpenes, CV-grown sweet pepper fruits showed the lowest presence of sesquiterpenes compared to the other samples, suggesting their poor contribution to the aromatic intensity of the vegetables. The characterizing terpene was 3-carene, which represents almost half of the entire class, followed by _trans_-caren-3-ol while, among the sesquiterpenes, \(\beta\)-curcumene is the compound that most contributed to the aromatic profile, followed by a contained presence of \(\alpha\)-santalene. The CO samples contained, albeit very small, both 3-carene and _trans_-caren-3-ol and an intra-class inversion in favor of sesquiterpenes, which is the most consistent and entirely represented by \(\alpha\)-santalene followed by \(\beta\)-curcumene. A similar pattern was observed in the control and in HD treated red _Topepo_ fruits in which the main compounds were 3-carene and the _trans_-caren-3-ol, although in lower concentrations compared to CV. Among the sesquiterpenes, \(\alpha\)-copaene and \(\beta\)-curcumene were detected. Aldehydes (E, Z)-2,6-nonadienal, (Z)-2-nonenal, and 7,11-hexadecadienal were also present in all samples. CO had the highest quantity of hexanal, while CTR contained high quantity of _cis_-decenal. Among the esters,