## 3 Results and Discussion
### Profile of Volatile Aroma Compounds in Raw and Dried B. edulis Mushrooms by HS-ITEX/GC-MS Analysis  
The aroma of mushrooms is given by a combination of volatile and non-volatile compounds of different chemical structures, such as alcohols, ketones, esters, aldehydes, hydrocarbons, acids, and heterocyclic and aromatic molecules [6]. As indicated in Table 3, 15 aroma compounds were detected by HS-ITEX/GC-MS in raw _B. edulis_ samples, 16 aroma compounds in samples dried by the HAD technique, and 10 aroma compounds in samples dried by the CVD method. A more diverse composition of aroma compounds was identified in HAD powders. The most abundant aroma compounds identified in the raw sample were 1-octen-3-ol (70.52 \(\pm\) 1.13%), 2-methyl-2-butenal (11.88 \(\pm\) 0.15%), 1-octen-3-one (9.06 \(\pm\) 0.11%), and (E)-2-octenal (5.74 \(\pm\) 0.06%). From the odor point of view, among C8 aroma compounds, 1-octen-3-ol and 1-octen-3-one have been described as being \"earthy/mushroom-like\", while different attributes have been given to the others, as following: (E)-2-octenal--green, \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**No.**} & \multirow{2}{*}{**Compound**} & \multicolumn{4}{c}{**Content (\%)**} \\ \cline{3-5}  & & **Raw Sample** & **Dried by HAD** & **Dried by CVD** \\ \hline \multirow{4}{*}{1} & \multirow{4}{*}{3-Methyl-1-butanol} & Alcohols & \multirow{4}{*}{0.28 \(\pm\) 0.04} & \multirow{4}{*}{0.37 \(\pm\) 0.03} \\  & & 1.7-Octadien-3-ol & & 0.03 \(\pm\) 0.001 & \\  & & 1.0-Octadien-3-ol & & 0.16 \(\pm\) 0.01 & \\  & 1-Octanol & nd & 0.16 \(\pm\) 0.01 & \\  & 4 & 1-Octen-3-ol & & 91.71 \(\pm\) 1.32 & 91.25 \(\pm\) 1.41 \\  & 5 & \(\ell\)-2-Octen-1-ol & & 0.04 \(\pm\) 0.001 & 0.20 \(\pm\) 0.01 & \\  & 6 & (\(\chi\))-2-Octen-1-ol & & 1.12 \(\pm\) 0.03 & 2.48 \(\pm\) 0.09 & 2.99 \(\pm\) 0.03 \\  & 7 & Octen-1-ol & & nd & 0.22 \(\pm\) 0.02 & \\  & 8 & (\(\chi\))-3-Octen-1-ol, & & nd & 0.07 \(\pm\) 0.001 & nd \\  & acetate & & Aldehydes & & \\
9 & Benzaldehyde & 0.20 \(\pm\) 0.008 & 0.10 \(\pm\) 0.001 & \\  & Benzene & nd & 0.30 \(\pm\) 0.01 & 0.20 \(\pm\) 0.02 \\  & acetaldehyde & nd & & & \\
11 & Dodecanal & 0.03 \(\pm\) 0.001 & nd & & \\
12 & 2-Ethyl-2-hexenal & nd & 0.28 \(\pm\) 0.03 & nd \\  & 2-Ethyl-\(trans\)-2- & & 0.29 \(\pm\) 0.01 & nd & nd \\
13 & butenal & nd & 0.39 \(\pm\) 0.39 & 0.41 \(\pm\) 0.02 \\
14 & Hepanal & 0.41 \(\pm\) 0.01 & 0.98 \(\pm\) 0.04 & 1.44 \(\pm\) 0.02 \\
15 & Hepanal & 11.88 \(\pm\) 0.15 & nd & nd \\
16 & 2-Methyl-2-bleenal & 0.12 \(\pm\) 0.02 & nd & & nd \\
18 & Nomanal & 0.07 \(\pm\) 0.001 & nd & & nd \\
19 & (\(E\))-2-Octenal & 5.74 \(\pm\) 0.06 & nd & nd \\
20 & (\(E\))-2-Pentenal & 0.16 \(\pm\) 0.02 & 1.61 \(\pm\) 0.02 & nd \\  & Ketones & & & \\
21 & 2-Heptanone & nd & 0.61 \(\pm\) 0.02 & 0.59 \(\pm\) 0.04 \\
22 & 3-Octanone & 0.34 \(\pm\) 0.05 & nd & nd \\
23 & 1-Octen-3-one & 9.06 \(\pm\) 0.11 & nd & nd \\  & Others (hydrocarbons, sesquiterpenness, sulfur compounds, etc.) & & \\
24 & Caryophyllene & nd & 0.07 \(\pm\) 0.001 & nd \\
25 & Dimethyl disulfide & nd & & 1.59 \(\pm\) 0.02 \\
26 & D-Limonene & nd & 0.52 \(\pm\) 0.04 & 0.35 \(\pm\) 0.04 \\
27 & 2-rt-Penty-furan & nd & nd & 0.82 \(\pm\) 0.09 \\ \hline \hline \end{tabular} nd = not detected.  
\end{table} 
Table 3: Mean relative peak areas (expressed as % from total peak areas) of aroma compounds from raw and dried _B. edulis_ mushrooms as determined by HS-ITEX/GC-MS; data values are mean \(\pm\) SD. fatty\"; 3-octanone--\"sweet, fruity, musty\"; 1-octanol--\"detergent, soap, orange-like\"; (E)-2-octen-1-ol--\"grass-like\"; and 1-octen-3-one also \"metallic\" [6; 40]. The aroma profile of fresh edible mushrooms may vary according to their maturity [6], storage time and temperature, and analysis techniques [41]. An increase of the diversity of aroma compounds have been recorded with the drying process of raw wild _B. edulis_. The only aroma compounds commonly identified both in raw and dried samples, but at different extents, were hexanal, 1-octen-3-ol, and (Z)-2-octen-1-ol.