## 2 Results
### Identification of Compounds with Sensory Activity Using GC-O-MS

Table 4: Compounds extracted using HS-SPME and HS-SPE tentatively identified via GC-O-MS with their calculated retention index (RI(E)), library retention index (RI), CAS, percentage of modified frequencies (%MF), and aroma descriptor [9, 17]. N.I: The compound shows sensory activity, but it was not possible to make the proper identification; N.D: sensory activity was felt with a single sample preparation technique; much of the data were obtained in: [[http://www.thegoodscentscompany.com/index.html](http://www.thegoodscentscompany.com/index.html)]([http://www.thegoodscentscompany.com/index.html](http://www.thegoodscentscompany.com/index.html)), accessed on 11 March 2023. A total of 45 compounds with sensory activity were extracted using these techniques, of which 42 were tentatively identified (Table 4). Most of these compounds are detected in traditional coffee beverages [9; 17]. The results revealed the presence of a variety of compounds, both common in traditional coffee beverages and less common or present at low concentrations. These compounds offer aromatic notes ranging from fruity to sweet and phenolic compounds. With approximately fourteen compounds with sweet notes, nine toasted, seven fruity, seven woody, five floral, and five green, the documented information in the literature is reinforced, highlighting the sensory affinity of CB with sweeter and fruitiier aromatic notes, as well as the absence of burnt notes. The identification of these sensory-active compounds not only establishes a solid foundation for understanding the aromatic profile but also contributes to advancing knowledge in this research field. Compounds with significantly high modified frequency percentages, such as ethanone, 1-(2-furanyl), ethanone, 1-(2-thienyl), \(\gamma\)-Butyrolactone, 2-Buten-1-one, 1-(2,6,6-trimethyl-1,3-cyclohexadien-1-yl), 1\(H\)-Pyrrole, 1-(2-furanyl methyl), were identified. These compounds are not typical in coffee and are found at deficient concentrations. It is hypothesized that this phenomenon could be related to the high quality of coffee, or the preparation methodology used, which could facilitate the extraction of these uncommon compounds. Other analytical methods are necessary to obtain more conclusive results regarding these phenomena, and an additional methodology should be established to quantify the presence and concentration of these compounds more precisely [2]. Another relevant observation is the detection of compounds with fruity, sweet, green, and other descriptors, such as linalool oxide/(Z)-linalool oxide, Furfural, Ethanone, 1-(2-furanyl), benzaldehyde, 5-methylfuran-2-carbaldehyde, Butyrolactone, 2-Buten-1-one, 1-(2,6,6-trimethyl-1,3-cyclohexadien-1-yl), Phenol, 2-methoxy, Benzyl alcohol, Furan, 2,2\({}^{\prime}\)-[oxybis(methylene)]bis, 1H-Pyrrole-2-carboxaldehyde, and 2-Methoxy-4-vinylphenol, among others. These compounds are common in fruit, wine, and liquor matrices. These findings align with literature assertions describing CB with fruity, sweet, chocolate, and viinous notes [1; 5]. Finally, the one retention time of the aromatic signals could not be assigned to the specific compounds. There were two main reasons for this finding. First, none of the results obtained from the NIST19 database showed retention indices close to those of the chromatograms. These compounds are relatively rare in the aromatic composition of coffee. This result could be attributed to the limited resolution of the mass detector and the relatively common mass/charge ratios (\(m/z\)) of these compounds, which make their precise assignment difficult. Additionally, two of these compounds had modified frequency percentages (%MF) below 50%, indicating that their relevance to the aroma of CB was limited. The compounds identified by comparing the mass spectra and the NIST19 database are shown in Table S4 [10]. A comparison of HS-SPME and HS-SPE extraction techniques revealed an intriguing complementarity in compound identification.