## 3 Results and Discussion
#### 3.4.7 Others  
Furans predominantly form from the oxidation of dehydrated carbohydrates and fatty acids or through the Amadori rearrangement pathway [41]. For instance, 2-pentylfuran exhibits a caramel-like, burnt, woody flavor from fatty acid oxidation [42]. Additionally, 2-pentylfuran possesses a low odor-detection threshold and significantly contributes to the aroma of the sample. Pyrazine, a low-odor ketone produced through Strecker degradation, enriches the aroma of chicken with _Armillaria mellea_ prepared via pressure cooking [20]. Indoles with a high odor-detection threshold, imparting a floral aroma [40], and certain myristic aldehydes in S30 generate myristyl ethers through heating. The OAV of significant volatile flavor compounds notably varies across the five samples (\(p<0.05\)); the cumulative OAVs of 28 compounds (key volatile flavor compounds) exceed 1. Aroma characteristics undergo considerable changes due to substantial shifts in the samples' volatile compound content during the pressure-cooking process. While the odors of the remaining three volatile compounds have not yet been described, the aromas of these essential volatile compounds can serve as distinctive scents of chicken with _Armillaria mellea_ prepared via pressure cooking. In addition, while the remaining sixteen compounds possess aromatic qualities, they function primarily as fragrance enhancers and do not exhibit the distinctive odors of chicken with _Armillaria mellea_ prepared via pressure cooking. Nonanal, decanal, (E,E)-2,4-nonadienal, (E,E)-2,4-decadienal, and 1-octen-3-ol are highlighted as the main volatile compounds responsible for the volatile flavor of chicken with _Armillaria mellea_ prepared via pressure cooking. These compounds have low odor-detection thresholds and relatively high relative contents. Furthermore, the balance of and interaction between volatile organic molecules can be changed by appropriately adjusting the pressure-cooking period, which will impart a distinct aroma to the samples. Analysis of Differences in the Content of Volatile Compounds in Chicken with Armillaria mellea During the Pressure-Cooking Process by GC-IMS  
Integrating multiple instrumental measurements is essential to obtain a more comprehensive understanding of volatile compounds. Using GC-IMS to analyze the volatile constituents of chicken with _Armillaria mellea_ prepared via pressure cooking under varying pressure-cooking durations, we found that most signals appeared within a drift time range of 0.4-1.6 (Figures 6a and 7b). Although 99 peaks were detected, only 81 volatile compounds were identified, with some compounds showing multiple signals (monomers and dimers) due to ion and neutral molecule admixtures [43]. Benzaldehyde, nonanal, ammonia, heptanal, 2-heptanone, 1-butanol, (Z)-2-pentenal, 2-methyl-1-propanol, and hexanal exhibit monomers and dimers with similar retention times but different drift times (e.g., RtAmmonia monomer = 705.706 and RtAmmonia dimer = 703.863; DtAmmonia monomer = 0.91082 and DtAmmonia dimer = 0.85187). Additionally, nine signal peaks remained unidentified, comprising a total of 23 aldehydes, 18 alcohols, 10 esters, 10 heterocyclic compounds, 1 organic acid, 10 ketones, 6 terpen, 2 ether species, and 1 other species (Figure 7c and Supplementary Table S3). The differences in the classes and concentrations of volatile compounds detected by the two GC-based methods could be attributed to the different sampling and detection techniques. Therefore, in comparison with the GC-MS technique, only 16 volatile compounds, including phenylacetaldehyde, 1-octanol, benzaldehyde, 1-octen-3-ol, nonanal, 1-hexanol, (E)-2-heptenal, octanal, 1-pentanol, (E)-2-hexenal, heptanal, ethyl pentanoate, hexanal, pentanal, 3-methylbutanal, and decanal, were present in both methods. Figure 6: Analysis of volatile compounds, using topographic map, in chicken with _Armillaria mellae_ prepared via pressure cooking.