# Effects of Drying Process on the Volatile and Non-Volatile Flavor Compounds of _Lentinual edodes_
## 3 Results and Discussion
### HS-SPME-GC-MS Analysis of Volatile Compounds of L. edodes
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Compounds**} & \multirow{2}{*}{**RI a**} & \multicolumn{6}{c}{**Contents (\(\upmu\)g/g)**} & \multirow{2}{*}{**ID e**} \\ \cline{3-6}  & & & **F b** & & **FD** & **HAD** & **ND** \\ \hline
1-Hexanol & 871 & nd d & 0.40 & 0.56 & 1.17 & A \\
1-Octen-3-ol c & 983 & 857.02 & 103.78 & 5.72 & 105.30 & B \\
2-Cyclohexen-1-ol & 985 & nd & nd & 7.22 & nd & A \\
3-Octanol c & 998 & 6.09 & 1.93 & nd & 1.40 & B \\
2-Octen-1-ol c & 1071 & 132.99 & 6.35 & 2.59 & 13.86 & B \\
1-Octanol c & 1077 & 19.89 & 1.99 & 0.68 & 2.06 & B \\
**Alcohols (11)** & 1100 & nd & 2.13 & nd & nd & A \\ Phenylethyl Alcohol & 1117 & nd & 0.08 & 0.95 & nd & A \\
4-Methyl-benzeneethanol & 1173 & nd & nd & 0.66 & nd & A \\ \(\alpha\)-Terpineol & 1188 & nd & 0.43 & nd & nd & B \\ Cedrol & 1596 & nd & 0.11 & nd & nd & B \\
**_Total alcohols_** & & 1015.99 & 117.20 & 18.39 & 123.79 & \\ \hline Hexanal & 803 & nd & 0.34 & 4.62 & 0.02 & A \\  & (E)-Hept-2-enal & 958 & nd & nd & nd & 0.18 & A \\ Benzaldehyde & 965 & 0.69 & 0.62 & 1.30 & 0.15 & A \\ Octanal c & 1004 & nd & nd & 0.18 & nd & A \\
**Aldehydes (9)** & Benzeneacetaldehyde & 1046 & 0.48 & 3.44 & 0.93 & 0.32 & A \\ (E)-2-Octenal c & 1058 & 11.78 & nd & 1.76 & 1.72 & A \\
2-Phenylpropenal & 1157 & nd & 0.67 & 5.64 & 0.07 & A \\ Decanal & 1206 & 0.69 & 0.42 & 0.27 & 0.09 & A \\ (z)-3,7-Dimethylocta-2,6-dienal & 1241 & nd & 1.18 & nd & nd & A \\
**_Total aldehydes_** & & 13.64 & 6.67 & 14.70 & 2.55 & \\ \hline \multirow{10}{*}{**Ketones (6)**} & 1-Octen-3-one c & 981 & 237.99 & 5.52 & 21.17 & 118.24 & B \\
3-Octanone c & 991 & 6.09 & 11.61 & 6.79 & nd & B \\
3-Octen-2-one c & 1042 & nd & nd & nd & 0.11 & A \\ Acethoneone & 1066 & nd & nd & 0.14 & 0.02 & A \\ (+)-Cambphor & 1139 & 0.18 & 0.08 & 0.05 & 0.02 & B \\
2-Undecanone & 1297 & nd & 0.06 & 0.34 & 0.01 & A \\
**_Total ketones_** & & 244.26 & 17.27 & 28.49 & 118.40 & \\ \hline \multirow{10}{*}{**Sulfur**} & Carbon disulfide & \textless{}700 & 148.36 & 12.51 & 66.31 & 11.01 & A \\  & Dimethyl disulfide & 700 & nd & nd & 2.58 & nd & B \\ \cline{1-1}  & Dimethyl trisulfide & 973 & nd & 0.80 & 0.26 & nd & B \\ \cline{1-1}  & 1,2,4-Tritihiolane & 1083 & 7.00 & 2.79 & 32.21 & nd & B \\ \cline{1-1}  & 2,4,5-Tritihiolanex & 1121 & nd & nd & 4.87 & nd & A \\ \cline{1-1}  & Dimethyl tetrasulfide & 1209 & nd & nd & 2.27 & nd & A \\ \cline{1-1}  & 1,2,4,5-Triethionine & 1362 & nd & 0.11 & 7.23 & nd & B \\ \cline{1-1}  & 1,2,4,6-Tetrathiophene & 1504 & nd & 0.01 & 3.22 & nd & B \\ \cline{1-1}  & Lenthionine & 1615 & 0.24 & 1.00 & 17.11 & 0.04 & B \\ \cline{1-1}  & Hexathiepane & 1615 & nd & nd & 0.25 & nd & B \\ \cline{1-1}  & Cyclic octaatomic sulfur & 2000 & nd & nd & 0.29 & nd & A \\ \cline{1-1}  & _Total sulfur compounds_ & & 155.60 & 17.22 & 136.60 & 11.05 & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Contents of volatile compounds in fresh and different dried _L. edodes._It has been reported that alcohols, aldehydes and ketones played important roles in flavor profiles of foods [9; 10; 23; 24]. As shown in Table 1, the contents of alcohols, aldehydes and ketones in fresh, FD, HAD and ND were 1273.89 \(\mu\)g/g, 141.14 \(\mu\)g/g, 61.58 \(\mu\)g/g, and 244.74 \(\mu\)g/g, respectively. However, the contents of alcohols and ketones significantly decreased after the drying process. Similar results were reported in other mushrooms [9; 10]. As shown in Figure 2, alcohols were the highest in fresh samples, but decreases were shown, especially in HAD mushroom samples. The content of aldehydes in HAD mushroom samples increased slightly in comparison with fresh samples. This may be due to aldehydes mainly derived from the oxidation and degradation of unsaturated fatty acids [25]. In addition, increasing the temperature of _L. eodes_ samples may also promote Maillard reaction, including Strecker degradation, which increased aldehyde content [26]. The content of ketones in FD samples was the lowest.