## 2 Results and Discussion
### Volatile Compounds

Table 5: _Cont._The most abundant alcohol identified in _P. serotina_ seeds was 2,3-butanediol, which was also the major volatile compound in raw (17.03 ppm) and toasted seeds (17.44 ppm). This alcohol is the major volatile component of sweet kernels and has been associated to their characteristic taste [34]. 2,3-butanediol is also found in cheeses [45] and honey [46]. Recently, it has been reported that this metabolite is abundant in roasted _Trichosanthes kirilowii_ seeds, however it was absent in the raw seeds, which suggests that 2,3-butanediol was generated during the toasting process [47]. In contrast, our results indicated that 2,3-butanediol levels in black cherry seeds were not significantly different before and after toasting. Benzyl alcohol, predominantly found in toasted seeds, imparts a sharp, burning taste and a faint aroma in toasted almonds [48]. This compound was previously detected as one of the major volatiles of black cherry leaves and also displays a vasodilator effect [8]. Regarding 1-pentanol, detected in both raw and toasted seeds, it has been proposed that it derives from the oxidation of linoleic acid, and its concentration increases with storage time in almonds [49]. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multicolumn{2}{c}{**RI**} & \multicolumn{2}{c}{**RI**} & \multirow{2}{*}{**Compound**} & \multirow{2}{*}{**Raw**\({}^{\text{c}}\)} & \multirow{2}{*}{**Toasted**\({}^{\text{c}}\)} & \multirow{2}{*}{**ID**\({}^{\text{c}}\)} \\ \cline{5-6} \multicolumn{2}{c}{**Calculated**\({}^{\text{a}}\)} & & & & & & \\ \hline
**DB5** & **WAX** & **DB5** & **WAX** & & **(ppm \({}^{\text{d}}\))** & **(ppm \({}^{\text{d}}\))** & \\ \hline \multicolumn{6}{c}{**Pyrroles and Furans**} \\
811 & 1165 & 811 & 1168 & 1H-Pyrrole, 1-ethyl- & & 0.144 & MS, RI \\
847 & & 841 & 1H-Pyrrole, 3-methyl- & & 0.082 & MS, RI \\
948 & & & & 1H-Pyrrole, 1-butyl- & & 0.021 & MS \\
891 & 1122 & 892.1 & 1123 & 2-\(n\)-Butylfuran & & 0.707 & MS, RI \\
991 & 1211 & 991 & 1213 & Furan, 2-pentyl- & 0.077 & 0.236 & MS, RI \\
1037 & & & & 2,3-Dihydrofuran & & 0.008 & MS \\
1016 & 2004 & 1016 & 2006 & 1H-Pyrrole-2-carboxaldehyde & & 0.114 & MS, RI \\
1076 & 2020 & 1076 & 2020 & 2-Pyrrolidinone & & 0.477 & MS, RI \\  & 1675 & & 1678 & 2-Pyrrolidinone, 1-methyl- & & 0.057 & MS, RI \\  & & & & & & \\  & 632 & & 643 & Methanethiol & & 0.046 & MS \\
559 & 701 & & Dimethyl sulfide & 0.052 & 0.071 & MS \\
567 & & 531 & & Methylene chloride & 0.844 & 0.474 & MS \\
612 & 1009 & 615 & 1010 & Trichlormethane & 0.059 & 0.028 & MS, RI \\
724 & & & & Propanamide, _N,N_-dimethyl- & 0.025 & MS \\
850 & & 850 & & Oxazole, trimethyl- & & 0.034 & MS, RI \\
1020 & & 1020 & & Benzene, 1,4-dichloro- & 0.450 & 0.253 & MS, RI \\  & 1419 & & & Benzene, 1,2-dichloro- & & 0.450 & MS \\  & 1710 & & & 6-Aminoidoline & & 0.136 & MS \\  & 1923 & & 1912 & Benzonitrile, 2-methyl- & & 0.060 & MS \\
1537 & & & & _N_-(2-Benzoyl-4-nitrophenyl)-4-_tert- & & & 0.041 & MS \\  & & & & butylbenzamide & & & \\  & 2051 & & Octaethylene glycol & 0.007 & MS \\ \hline \hline \multicolumn{6}{c}{Notes: \({}^{\text{a}}\) Calculated Kovats retention index on DB-5 or Wax column using a n-alkanes series; \({}^{\text{b}}\) Reported Kovats} \\ \multicolumn{6}{c}{retention index on library NIST; \({}^{\text{c}}\) Average of 3 replicates. Coefficient of variation \(<9.2\%\); \({}^{\text{d}}\) Semi-quantitative} \\ \multicolumn{6}{c}{values. \({}^{\text{e}}\) MS = tentative identification by comparison to mass spectra in NIST library, RI = identification by comparison of calculated Kovats retention index to that reported in literature.} \\ \end{tabular}
\end{table} 
Table 5: _Cont._Acetic acid was the main volatile carboxylic acid found in raw and toasted _P serotina_ seeds. This carboxylic acid can be regarded as a result of long-chain fatty acids degradation and it is often related to a strong sour odor [50]. Esters were detected in lesser quantities, some of them, such as methyl esters of short chain fatty acids, were found in raw seeds, but not in toasted seeds.