# New Insights on Volatile Components of _Vanilla planifolia_ Cultivated in Taiwan
## 2 Results
### Analysis of the Volatile Components of Taiwan-Cultivated Vanilla Pods Using HS-SPME
#### 2.2.3 Microorganism Treatments during the Curing Process
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multicolumn{1}{c}{\multirow{2}{*}{RI A}} & \multirow{2}{*}{**Compounds B**} & \multicolumn{4}{c}{**Relative Percentage C** (\%)a **} \\ \cline{2-7}  & & **Control** & \multicolumn{2}{c}{**Microorganism Treatment**} & \\ \cline{3-7}  & & **Ctrl E** & **Y1 E** & **Y2 E** & **Y3 E** & **B1**  \\ \hline
1250 & anise alcohol & 0.25 \(\pm\) 0.07a & 0.25 \(\pm\) 0.03a & 0.24 \(\pm\) 0.00a & 0.26 \(\pm\) 0.04a & 0.26 \(\pm\) 0.06a \\
1268 & cinnamic alcohol & 0.04 \(\pm  
The percentage of benzyl alcohol in Y2 was highest and resulted in floral and sweet aromas [25]. The minor components of the vanilla pods in the control group were low, with the exception of guaiaocl. These results are the same as those for natural vanilla pods sold abroad, and the main components of those pods are vanillin and guaiaocl [26]. The percentage of minor components in sample B was low, particularly for guaiaocl. Based on this, we speculated that the addition of _B. subtilis_ to vanilla pods results in a weaker smoky smell. Our findings confirm that the addition of microorganisms to vanilla pods affects their flavor [20]. To better understand the effects of different strains on the volatiles of vanilla pods, we performed principal component analysis (PCA) to observe the correlation between volatile components and samples (Figure 1). All component data in PCA was from Table 4. The statistical results divided the samples into three groups, primarily distinguishing the vanilla samples of _B. subtilis_ and _D. bruxellensis_. In regard to vanillin, there was not much diversity among all these groups, and the only obvious difference was for Y1. The percentage of vanillin in all samples was relatively high, thus suggesting that this compound was not an indicator component of any group and did not affect the classification of the samples. The component closest to B is 2-ethyl-1-hexanol, thus indicating that it is related to the addition of _B. subtilis_. The components closest to the Y1 sample are \(p\)-cresol and 2-pentylfuran, both of which exhibit lower percentage levels in the other vanilla samples. Using PCA, we inferred that the percentage of these two components was increased in response to the addition of _D. bruxellensis_. The four components that were closer to the control, Y2, and Y3 groups were guaiaocl, furfural, benzaldehyde, benzyl alcohol, and \(p\)-cresol, thus indicating that these four components are not affected by the addition of _B. subtilis_ or _D. bruxellensis_. Based on the statistical results presented above,  
Figure 1: Principal component analysis diagram of vanilla pods supplemented with different microorganism treatments. \(\blacktriangle\): Samples (ctrl: Standard procedure; Y1: _D. bruxellensis_; Y2: _S. cratagensis_; Y3: _C. cacaoi_; B: _B. subtilis_). \(\bullet\): Labeled volatile compounds. \(\Box\): Unlabeled volatile compounds. we can infer that the effects of _S. crataegensis_ and _C. cacaoi_ on vanilla are similar to those exerted by the microbial metabolic pathways of natural vanilla pods and that they belong to the same group as the control group. Vanilla pods processed with _D. bruxellensis_ and _B. subtilis_ exhibit different aromas due to the different metabolic pathways of these organisms, and this is consistent with the results of previous studies. The addition of this strain during the vanilla pod curing process produces \(\beta\)-glucosidase, a compound that affects flavor formation [21].