## 4 Conclusions  
In the present work, SPME-based aroma profiling of _Trebbiano d'Abruzzo_ and _Pecorino_ white wines was optimized through the combination of the DoE approach and RSM modeling of the total area of the GC chromatogram. In addition, to investigate the influence of the SPME conditions, (exposure time of the fiber to the sample headspace, sample temperature and concentration of added salt) on the relative contribution of the volatile components to the collected chromatogram, the peak areas of ethyl decanoate and 3-methyl-1-butanol were also modeled by DoE-RSM. The DVB/CAR/PDMS fiber was identified as the best one, since, compared to PDMS and CW/DVB sorbents, it allowed the extraction of a greater number of volatile components. The response surface of the total area of the chromatogram collected with the DVB/CAR/PDMS stationary phase exhibited two almost equivalent maximum conditions, at an NaCl concentration of 10% and T = 50 \({}^{\circ}\)C, and at an NaCl concentration of 30% and T = 30 \({}^{\circ}\)C. These maxima are both associated with the efficient extraction of esters from the wine sample. More specifically, the less volatile esters were preferentially extracted under the first experimental conditions, while the more volatile ones were preferentially extracted in the latter conditions. A preliminary comparison of the volatile profiles collected from _Trebbiano d'Abruzzo_ and _Pecorino_ samples did not provide a clear indication on the possibility of discriminating between these two varieties. Nevertheless, the SPME-based method optimized in the present investigation laid the foundations for a successive data-fusion approach, based on the combination of profiles of volatiles, organic acids, phenolics, and major elements, aimed at the varietal discrimination of wines produced with _Trebbiano d'Abruzzo_ grapes and with recently rediscovered autochthonous varieties belonging to the same family of grapes, including _Pecorino_.  
**Supplementary Materials:** The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/molecules28041534/s1](https://www.mdpi.com/article/10.3390/molecules28041534/s1)]([https://www.mdpi.com/article/10.3390/molecules28041534/s1](https://www.mdpi.com/article/10.3390/molecules28041534/s1)), Table S1. Retention time (RT) and experimental (exp) and literature (lit) retention index (RI) of each volatile compound; volatile profiles of PEC and TRE wine samples collected with the DVB/CAR/PDMS fiber under the optimized conditions: mean relative peak area (%) of each compound in the GC chromatogram with the related standard error in brackets. Table S2. Adjusted determination coefficients in fitting (R\({}_{\text{adj}}^{2}\)) and leave-one-out cross validation (Q\({}_{\text{adj}}^{2}\)), and ANOVA for the response surface model of the total area of the GC chromatogram (A\({}_{\text{TOT}}\)), and peak areas of ethyl decanoate (A\({}_{\text{ED}}\)) and 3-methyl-1-butanol (A\({}_{\text{MB}}\)) collected with the PDMS and DVB/CAR/PDMS fibers.  
**Author Contributions:** Conceptualization, A.A.D. and L.R.; methodology, L.R.; software, M.F.; validation, M.F. and A.B.; formal analysis, M.F.; investigation, M.A.M.; data curation, M.F. and L.R.; writing--original draft preparation, A.A.D.; writing--review and editing, A.A.D. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received no external funding.  
**Institutional Review Board Statement:** Not applicable.  
**Data Availability Statement:** Not applicable.  
**Conflicts of Interest:** Author [PERSON] was employed by the company Hortus Novus. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.