## 3 Results and Discussion
### Effects of Processing Time and Muscle Type on Lipolysis and Proteolysis in Smoked Dry-Cured Ham  
During the processing of dry-cured ham, the major components of IMF (triglycerides and phospholipids) undergo an intense lipolysis. Free fatty acids (FFAs) are lipolysis products that affect the final organoleptic characteristics of dry-cured ham. FAAs are precursors of several volatile compounds due to their susceptibility to oxidation [16]. Primary products of lipid oxidation, hydroperoxides, are degraded into secondary oxidation products (aldehydes, ketones, esters, and many others) by a series of complex reactions [41]. A moderate degree of lipid oxidation can have a positive effect on the development of the typical flavor of raw ham, while a higher degree of lipid oxidation leads to an impairment of the nutritional, functional, and sensory properties [2; 6; 16]. Several factors such as pH, a\({}_{w}\), NaCl, temperature, and location of the muscle can influence the intramuscular lipids oxidation [16]. The results of lipid oxidation by TBARS method in two muscles (BF and SM) \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Muscle (M)** &
\begin{tabular}{c} **Phase of** \\ **Production (P)** \\ \end{tabular} & \(\mathbf{M\times P}\) \\ \hline \multicolumn{4}{c}{**Physicochemical parameter**} \\ Water & 0.000 & 0.000 & 0.000 \\ Intramuscular fat & 0.000 & 0.000 & 0.000 \\ Protein & 0.156 & 0.000 & 0.000 \\ Ash & 0.000 & 0.000 & 0.000 \\ NaCl & 0.000 & 0.000 & 0.000 \\ a\({}_{w}\) & 0.000 & 0.000 & 0.000 \\ pH & 0.166 & 0.020 & 0.329 \\ mg MDA/kg sample & 0.003 & 0.000 & 0.708 \\ Proteolysis index & 0.004 & 0.000 & 0.003 \\ \hline \multicolumn{4}{c}{**Color parameters**} \\ L\({}^{*}\) & 0.000 & 0.000 & 0.000 \\ a\({}^{*}\) & 0.000 & 0.000 & 0.005 \\ b\({}^{*}\) & 0.001 & 0.000 & 0.283 \\ \hline \multicolumn{4}{c}{**Texture parameters**} \\ Hardness (N) & 0.000 & 0.000 & 0.000 \\ Gumminess (N) & 0.000 & 0.000 & 0.000 \\ Chewiness (N \(\times\) mm) & 0.000 & 0.000 & 0.000 \\ Adhesiveness (N \(\times\) mm) & 0.000 & 0.000 & 0.000 \\ Springiness (mm) & 0.000 & 0.000 & 0.301 \\ Cohesiveness & 0.965 & 0.000 & 0.040 \\ Resilience & 0.011 & 0.000 & 0.000 \\ \hline \multicolumn{4}{c}{**Volatiles**} \\ Aldehydes & 0.000 & 0.000 & 0.000 \\ Alcohols & 0.000 & 0.000 & 0.000 \\ Ketones & 0.000 & 0.000 & 0.011 \\ Aromatic hydrocarbons & 0.047 & 0.000 & 0.000 \\ Esters & 0.010 & 0.000 & 0.000 \\ Aliphatic hydrocarbons & 0.539 & 0.000 & 0.231 \\ Phenols & 0.000 & 0.000 & 0.000 \\ Terpenes & 0.000 & 0.000 & 0.000 \\ \hline \hline \end{tabular} \(p\)-values are obtained by general linear model (GLM) test, at 95% confidence level. Significance levels: \(p>0.05\), not significant; \(p<0.05\), significant.  
\end{table} 
Table 4: \(p\)-value for each physicochemical parameter as obtained by GLM analysis. are shown in Figure 1A. Lipid oxidation increased significantly (\(p<0.05\)) throughout the production process, from 0.13 to 0.45 mg MDA/kg sample in BF and from 0.13 to 0.52 mg MDA/kg sample in SM. TBARS values remained constant (\(p>0.05\)) until the ripening phase, when a significant (\(p<0.05\)) increase was observed in both muscles. A similar behavior was also observed in the production of Celta ham [8], where the authors observed the increase in malonaldehyde content during post-salting and dry-ripening (\(\sim\)130 and 245 d of processing). We can assume that an increase in malonalidehyde content occurred slightly later due to the antioxidant effect of smoking. In other studies, increased TBARS values were also observed during the initial production phases of Bayonne [9] and Parma [42] hams. In contrast to our results, the two above mentioned studies reported a sharp decrease in TBARS levels in BF and SM towards the end of the process, which authors [9; 42] ascribed to the degradation of unstable aldehydes to volatile compounds and the formation of Schiff bases. SM had significantly (\(p<0.05\)) higher TBARS values than BF at the end of processing.