## 4 Discussion  
The large variability regarding the composition of edible vegetable oils is reflected by many reports and publications, as presented above. Therefore, it is very difficult to compare data released from different European regions, even for the same type of oils, since the botanical variety of the oil raw sources (seeds or fruits), the geographic location and environment conditions, the fractions used to produce the oil (seeds or pulp or whole fruit) and the technological parameters are strongly influencing their final composition. The data presented here reflected mainly the composition of oils manufactured in Romania, at low scale (the authentic ones) or industrial scale. Their composition did not differ significantly, although the commercial samples had some quantitative differences for the five phytochemical categories. Figure 5: (**a**) PLSDA score plot for the discriminatory analysis of the eight categories of oils, considering their content in phenolic derivatives. (**b**) Heatmap representing the Euclidian distance, and by the Ward algorithm, the similarities between individual oil samples inside a group and among groups. The data obtained by HPLC-DAD-RF-MS and GC-MS, complemented with statistical multivariate analysis, brings added value for the discrimination, classification, and authentication of these edible oils. These results are complementary and in good agreement with our previous studies using the ATR-FTIR spectrometry coupled with chemometrics [25]. The univariate analysis using one-way ANOVA and [PERSON]'s HSD post-hoc test combined with multivariate analysis showed significant discriminations among oils used in this study, either their botanical authentication, or their individual variations due to processing parameters. The profiles of fatty acids (Figure 1a) show similarities between SO and PO oils, represented mainly by C18:0. LSO is represented mainly by C18:3n-3, while WO by C18:2n-6 and EVOOs by C18:1n-9. Specifically, SFO was identified by C22:0 and C18:2n-6, while HO by C18:3n-6 (\(\gamma\)-linoleic acid) and C20:0, and finally, SBO by C16:0, C16:1n-7 and C18:1n-9. Our data were compared to other publications, as presented in Section 3.2, the average levels of fatty acids being similar, in spite of their different origins. For volatiles, the heatmap shows a good discrimination between the profiles of the eight oil groups, especially between EVOO, SFO, SBO. Stronger discriminations were observed between SFO (rich in 2-octene, acetophenone, \(\alpha\)- and \(\beta\)-pinene), for EVOOs rich in hexyl derivatives (hexenol, hexenol, hexyl acetate), and for SBO, rich in volatile acids (butanoic, hexanoic, butanoic), heptanal and oimen. WO, LSO and SO showed less significant biomarkers, while HO was represented by a higher content of hexanal and PO by octene and pinenes. Few data were reported about volatiles responsible for the sensorial characteristics of these oils, but generally they were similar, mainly for olive oils [43; 44; 45], but also for lineseds [36] and walnut [39; 40]. Beside the relevance of volatiles for the oil origin and identity, one can also consider the influence of the thermal processing on volatiles' elaboration, their different sensorial characteristics being due not only to the raw material, but also to technological parameters (temperature-time and storage conditions). Concerning carotenoid pigments, HO was the richest source of \(\beta\)- and \(\alpha\)-carotene and luteoxanthin, while SO was the richest in \(\beta\)-carotene epoxides. The LSO was identified easily by a high content in auoxanthin and violaxanthin, beside \(\beta\)-carotene epoxides. The samples EVOO had lower levels of auoxanthin, violaxanthin and \(\alpha\)-carotene' By far, the richest content of carotenoids, especially zeaxanthin, lutein, \(\beta\)-carotene and \(\beta\)-cryptoxanthin was reported in SBO, followed by WO, EVOO, and in lower amounts in SO.