## 3 Results and Discussion
### Analysis of Volatile Compounds
#### 3.7.1 Volatile Compounds Content

Table 3: _Cont._  
\begin{table}
\begin{tabular}{c c c c c c} \hline \multicolumn{1}{c}{**Volatile Compounds**} & \multicolumn{1}{c}{**RI**} & \multicolumn{2}{c}{**Normal Ham**} & \multicolumn{2}{c}{**Spolled Ham**} \\ \cline{2-6}  & **Bf** & **SM** & **BF** & **SM** & **BF** & **SM** \\ \hline
82 & Phenol & 2008 & 6.76 \(\pm\) 0.48 \({}^{\rm a}\) & 3.8 \(\pm\) 1.28 \({}^{\rm b}\) & ND & ND \\  & Total & & 3.32 \(\pm\) 0.10 \({}^{\rm Ba}\) & 2.07 \(\pm\) 0.91 \({}^{\rm Ba}\) & 24.04 \(\pm\) 3.2 \({}^{\rm Aa}\) & 192 \(\pm\) 5.16 \({}^{\rm ab}\) \\ \cline{2-6} Trepenes & & & & & \\
83 & Cyclocotetarence & 1316 & 8.44 \(\pm\) 0.92 & ND & ND & ND \\
84 & Longliotene & 1378 & 6.64 \(\pm\) 0.96 \({}^{\rm a}\) & 7.56 \(\pm\) 1.32 \({}^{\rm a}\) & ND & ND \\
85 & Trans-2-Octenol & 1399 & 3.48 \(\pm\) 0.44 \({}^{\rm a}\) & 2.56 \(\pm\) 0.44 \({}^{\rm a}\) & ND & ND \\  & Total & & 18.92 \(\pm\) 2.32 \({}^{\rm a}\) & 10.12 \(\pm\) 1.76 \({}^{\rm b}\) & ND & ND \\ Others & & & & & \\
86 & Trimethylamine & 633 & ND & ND & 5.09 \(\pm\) 3.62 \({}^{\rm b}\) & 13.05 \(\pm\) 1.61 \({}^{\rm a}\) \\
87 & Carbon disulphide & 713 & 9.63 \(\pm\) 0.66 \({}^{\rm Aa}\) & 2.73 \(\pm\) 0.37 \({}^{\rm b}\) & 1.88 \(\pm\) 0.28 \({}^{\rm b}\) & 4.92 \(\pm\) 0.08 \({}^{\rm Aa}\) \\
88 & 2-Perstylfuran & 120 & 1.10 \(\pm\) 0.27 \({}^{\rm Ba}\) & 0.75 \(\pm\) 0.28 \({}^{\rm Ba}\) & 3.64 \(\pm\) 0.84 \({}^{\rm Aa}\) & 2.64 \(\pm\) 0.2 \({}^{\rm Aa}\) \\
89 & Hexennitrile & 1293 & 5.29 \(\pm\) 1.46 \({}^{\rm a}\) & 2.30 \(\pm\) 0.55 \({}^{\rm b}\) & ND & ND \\  & Total & & & & \\  & Total & & & & \\ \hline \multicolumn{6}{c}{\({}^{\rm a}\) Different typecAlcohols are one of the most abundant volatile compounds in dry-cured ham [40], with a total of 21 alcohols identified. Straight-chain fatty alcohols are formed through lipid oxidation reactions, while methyl-branched alcohols may result from the strecker degradation of amino acids [67]. Due to their low threshold, alcohols are often considered crucial contributors to the characteristic flavour of dry-cured meat products [68]. In this study, higher levels of alcohol were found in spoiled hams, where the total alcohol content in the BF of normal hams was higher than that of SM (\(p<0.05\)), consistent with a previous study on different muscles of Slovenian dry-cured hams [5]. Among the detected alcohols, ethanol exhibited the highest content (\(p<0.05\)). Due to its relatively high odour threshold, ethanol has been deemed insignificant in the overall flavour contribution of Jinhua ham [69]. It is noteworthy that methanethiol, characterised by a sewage odour and rotten cabbage scent, was exclusively present in spoiled ham [70]. According to a previous report by [PERSON] [71], intramuscular fat in meat plays an important role in preserving flavour by acting as a solvent for flavour compounds within the muscle tissue and facilitating subsequent reactions. Esters primarily form through the esterification reactions of carboxylic acids and alcohols. Short-chain esters contribute to fruity flavours, whereas long-chain esters are associated with fatty flavours [72]. The content of esters is generally low in Spanish and French dry-cured hams but higher in Italian Parma ham and homemade ham [73]. This may be due to the fact that nitrates, which inhibit lipid oxidation, are absent in the processing of Parma ham but are added to Spanish and French hams [74]. In this study, Xuanwei ham exhibited a higher ester content, likely also due to the absence of nitrate usage [60]. Moreover, the ester content was higher in the spoiled ham compared to the normal ham (\(p<0.05\)), consistent with a previous study on spoiled Jinhua ham [49]. Within the same quality grade of ham, BF showed higher ester content than SM, which is consistent with the results of a study on different muscles in smoked dry-cured ham [31]. Methyl isovalerate, ethyl isovalerate, and methyl pentanoate were identified as important odour-active esters in spoiled ham [49].