# Volatile Composition of Industrially Fermented Table Olives from Greece
## 4 Conclusions  
The results obtained from this study reveal the complex volatile profile of industrially fermented Halkidiki green olives, Conservolea and Kalamata natural black olives originating from different growing locations in Greece. More than 100 volatile compounds were identified in the pulp of olives and distributed over different chemical classes. All samples were rich in esters, alcohols and acids, whereas the samples of cv. Halkidiki were also rich in volatile phenols. Both qualitative and quantitative differences were observed between the olives produced from different cultivar as well as growing location. Based on multivariate analysis results, the samples were clearly separated according to olive cultivar and growing location. The table olives of the three cultivars were discriminated mostly due to the higher content of _trans_-\(\beta\)-ocimeime and ethanol in cv. Kalamata, \(\alpha\)-muvrolene and \(\alpha\)-faresene in cv. Conservolea and guiaicol and 4-methylguiaicol in cv. Halkidiki samples. Within the olives of cv. Conservolea, those grown in Magneas were clearly discriminated from the other two growing locations (Fthioida, N. Evia) due to their high content in butanoic acid, butanol, butanoate esters and volatile phenols (mainly guiaicol). Within the olives of cv. Halkidiki, those grown in Kavala were richer in volatile phenols, propanoate esters and propanoic acid, whereas the samples from the Halkidiki region were mainly associated with acetate, ethyl and methyl esters. Although fewer differences were observed between the cv. Kalamata olives from Aitoloakarnania and S. Peloponnese, there was a clear separation due to the higher content of 3-methylbutyl acetate, isobutyl acetate, methyl acetate and 3-methyl-1-butanol in S. Peloponnese samples, as well as to ethyl lactate and propyl hexanoate in Aitoloakarnania samples. To the best our knowledge, this is the first systematic study on the volatile composition of industrially fermented table olives from Greek cultivars, highlighting the pronounced effect of growing location. However, to confirm our results, further studies should be undertaken using a higher number of samples spanning different harvesting periods. Finally, the link between volatile compounds and microbial composition of table olives should be established that would  
Figure 5: OPLS-DA of the volatile compounds identified in cv. Kalamata natural black olives grown in Aitoloakarnania (AIT—red dots) and southern Peloponnese (PEL—green dots): (**a**) scores plot, and (**b**) loadings S-plot. The shaded areas represent the 95% confidence ellipses. The codes of variables are given in Table 2.  
enable the design of strategies to improve quality and enhance the regional character of the final product. The following are available online at [[https://www.mdpi.com/article/10.3390/foods10051000/s1](https://www.mdpi.com/article/10.3390/foods10051000/s1)]([https://www.mdpi.com/article/10.3390/foods10051000/s1](https://www.mdpi.com/article/10.3390/foods10051000/s1)), Table S1: Volatile compounds identified in the headspace of table olives from Kalamata, Conservolea and Halkidiki cultivars. Figure S1: Geographical origin of cv. Kalamata, cv. Conservolea and cv. Halkidiki table olives. Figure S2: PCA loadings plots of the volatile compounds identified in industrially fermented table olives from different cultivars: (**a**) Loadings 1 _vs_ Loadings 2; (**b**) Loadings 1 _vs_ Loadings 3. Figure S3: Heatmap plot of hierarchical cluster analysis performed on volatile compounds of table olives from CNS (cv. Conservolea), HLK (cv. Halkidiki) and KLM (cv. Kalamata) cultivars. Sample codes are given in Table 1. Variables codes are given in Table 2. Figure S4: Heatmap plot of hierarchical cluster analysis performed on volatile compounds of cv. Conservolea table olives from Northern Evia (EVIA), Fhiotida (FTH) and Magnexia (MAG) growing locations. Variables codes are given in Table 2. Figure S5: Principal component analysis of the volatile compounds identified in cv.