# Impact of Ageing on Pea Protein Volatile Compounds and Correlation with Odor
## 2 Results and Discussion
### Correlation between Instrumental Data and Odor
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Months** & **0** & **3** & **6** & **9** & **12** \\ \hline \multicolumn{5}{c}{**Treatment A (20 \({}^{\circ}\)C—Light)**} \\ \hline Hexanal & 5.1 \(\pm\) 0.2 \({}^{\mathrm{c}}\) & 10.7 \(\pm\) 0.3 \({}^{\mathrm{a}}\) & 10.1 \(\pm\) 0.1 \({}^{\mathrm{b}}\) & 4.1 \(\pm\) 0.2 \({}^{\mathrm{d}}\) & 3.7 \(\pm\) 0.1 \({}^{\mathrm{d}}\) \\ \hline Nonanal & 1.01 \(\pm\) 0.08 \({}^{\mathrm{c}}\) & 3.1 \(\pm\) 0.3 \({}^{\mathrm{a},\mathrm{b}}\) & 3.8 \(\pm\) 0.5 \({}^{\mathrm{a}}\) & 2.5 \(\pm\) 0.4 \({}^{\mathrm{b}}\) & 2.3 \(\pm\) 0.5 \({}^{\mathrm{b}}\) \\ \hline
2-nonenal & n.d. & n.d. & 0.72 & 0.66 \(\pm\) 0.07 & 0.58 \(\pm\) 0.06 \\ \hline
3-methylbutanal & n.d. & n.d. & n.d. & n.d. \\ \hline
1-octen-3-ol & 0.07 \(\pm\) 0.01 \({}^{\mathrm{d}}\) & 4.64 \(\pm\) 0.07 \({}^{\mathrm{b}}\) & 5.0 \(\pm\) 0.1 \({}^{\mathrm{a}}\) & 2.3 \(\pm\) 0.1 \({}^{\mathrm{c}}\) & 2.04 \(\pm\) 0.06 \({}^{\mathrm{c}}\) \\ \hline
3-octen-2-one & 0.08 \(\pm\) 0.05 \({}^{\mathrm{d}}\) & 24.5 \(\pm\) 0.5 \({}^{\mathrm{a}}\) & 18.1 \(\pm\) 0.6 \({}^{\mathrm{b}}\) & 7.1 \(\pm\) 0.2 \({}^{\mathrm{c}}\) & 6.6 \(\pm\) 0.3 \({}^{\mathrm{c}}\) \\ \hline
2-pentylfuran & 8.1 \(\pm\) 0.8 \({}^{\mathrm{a}}\) & 5.2 \(\pm\) 0.4 \({}^{\mathrm{b}}\) & 5.6 \(\pm\) 0.8 \({}^{\mathrm{b}}\) & 2.05 \(\pm\) 0.07 \({}^{\mathrm{c}}\) & 1.9 \(\pm\) 0.1 \({}^{\mathrm{c}}\) \\ \hline Benzaldehyde & 0.41 \(\pm\) 0.03 \({}^{\mathrm{b}}\) & 2.9 \(\pm\) 0.2 \({}^{\mathrm{b}}\) & 5 \(\pm\) 1 \({}^{\mathrm{b}}\) & 3.80 & 10 \(\pm\) 4 \({}^{\mathrm{a}}\) \\ \hline
2,5-dimethylpyrazine & n.d. & n.d. & n.d. & n.d. \\ \hline \multicolumn{5}{c}{**Treatment B (30 \({}^{\circ}\)C—Dark)**} \\ \hline Hexanal & 5.1 \(\pm\) 0.2 \({}^{\mathrm{b}}\) & 5.5 \(\pm\) 0.3 \({}^{\mathrm{b}}\) & 5.1 \(\pm\) 0.3 \({}^{\mathrm{b}}\) & 1.68 \(\pm\) 0.06 \({}^{\mathrm{c}}\) & 9.3 \(\pm\) 0.8 \({}^{\mathrm{a}}\) \\ \hline Nonanal & 1.01 \(\pm\) 0.08 \({}^{\mathrm{a}}\) & 0.84 \(\pm\) 0.08 \({}^{\mathrm{a}}\) & 0.56 \(\pm\) 0.01 \({}^{\mathrm{b}}\) & 0.31 \(\pm\) 0.03 \({}^{\mathrm{c}}\) & 0.9 \(\pm\) 0.1 \({}^{\mathrm{a}}\) \\ \hline
2-nonenal & n.d. & n.d. & n.d. & n.d. & n.d. \\ \hline
3-methylbutanal & n.d. & n.d. & n.d. & n.d. \\ \hline
1-octen-3-ol & 0.07 \(\pm\) 0.01 \({}^{\mathrm{b},c}\) & 0.10 \(\pm\) 0.01 \({}^{\mathrm{b}}\) & 0.088 \(\pm\) 0.004 \({}^{\mathrm{b}}\) & 0.05 \(\pm\) 0.01 \({}^{\mathrm{c}}\) & 0.24 \(\pm\) 0.02 \({}^{\mathrm{a}}\) \\ \hline
3-octen-2-one & 0.08 & 0.08 \(\pm\) 0.02 \({}^{\mathrm{c}}\) & 0.20 \(\pm\) 0.01 \({}^{\mathrm{b}}\) & 0.13 \(\pm\) 0.01 \({}^{\mathrm{c}}\) & 0.53 \(\pm\) 0.03 \({}^{\mathrm{a}}\) \\ \hline
2-pentylfuran & 8.1 \(\pm\) 0.8 \({}^{\mathrm{c}}\) & 10 \(\pm\) 1 \({}^{\mathrm{b}}\) & 11.1 \(\pm\) 0.7 \({}^{\mathrm{b}}\) & 9.5 \(\pm\) 0.5 \({}^{\mathrm{b},c}\) & 22 \(\pm\) 1 \({}^{\mathrm{a}}\) \\ \hline Benzaldehyde & 0.41 \(\pm\) 0.03 \({}^{\mathrm{c}}\) & 0.48 \(\pm\) 0.03 \({}^{\mathrm{b},c}\) & 0.55 \(\pm\) 0.02 \({}^{\mathrm{b}}\) & 0.46 \(\pm\) 0.03 \({}^{\mathrm{b},c}\) & 1.12 \(\pm\) 0.06 \({}^{\mathrm{a}}\) \\ \hline
2,5-dimethylpyrazine & n.d. & n.d. & n.d. & n.d. & n.d. \\ \hline \end{tabular}  
* \({}^{\mathrm{a}-d}\): Statistical groups for each compound in each sample during time; when no standard deviation was available, the compound was retrieved only in one of the three repetitions; n.d. = not detected; <0.05 = not quantified, below the quantification limit of the compound.  
\end{table} 
Table 3: Evolution of the nine compounds of interest during the ageing, in \(\mathrm{\SIUnitSymbolMicro g}\) of compound/g of sample (\(n=3\)). the ratio of the percentage of the cumulative amount of the different volatile compounds responsible for the descriptor, to the total amount of all volatile compounds. The evolution of these different sensory attributes during the two ageing conditions were presented in Figure 3.  
During treatment B (30 \({}^{\circ}\)C--Dark), the profile of volatile compounds sorted by sensory descriptor was slightly evolving.