# Physicochemical Properties and Oxidation Status of Pork from Three Rearing Systems
## 4 Discussion
### Physical Properties  
Color is an important attribute of meat quality for consumers. The results of meat brightness (L* value) in our work are in agreement with those of [PERSON] et al. [31], as meat from organic pigs was brighter than that from conventional pigs. In that study [31], it was found that the meat from organic pigs had higher CIE L*, a* and b* values than the meat from conventionally raised pigs. In contrast, [PERSON] and [PERSON] [32] reported that the meat from organically raised pigs was darker/redder in color, but the study acknowledged that the evidence for this was inconclusive. [PERSON] et al. [25] found that higher levels of animal welfare under organic farming reduce stress conditions and lead to reduced pH (lower levels of glycogen catabolized to lactic acid), and as a result the lightness value (L*) of organic meat increases. Our results are in line with this idea, as the pH of organic pork was significantly lower which elevated the L* value. Although redness scores (a*) of organic meat were the highest, the difference was not significant (\(p>0.05\)). Redder pork from organic systems could be attributed to a higher content of myoglobin. Heme pigments  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Parameters**} & \multicolumn{3}{c}{**Rearing Systems**} \\ \cline{2-4}  & **Organic** & **Conventional** & **Traditional** \\ \hline TBARS [mg/kg] & 1.24 \(\pm\) 0.54 a & 1.00 \(\pm\) 0.47 a & 0.41 \(\pm\) 0.16 b \\ Free fatty acids & 1.15 \(\pm\) 0.17 a & 0.58 \(\pm\) 0.10 c & 0.76 \(\pm\) 0.18 b \\ Antioxidant capacity & 26.42 \(\pm\) 1.98 b & 28.24 \(\pm\) 2.05 a & 27.50 \(\pm\) 1.30 a \\ \hline \hline \end{tabular} Values in the same row with different superscripts a, b, c are significantly different among organic, conventional and traditional pork.  
\end{table}
Table 4: Oxidation status of pork (mean \(\pm\) SD) from organic, conventional and traditional rearing systems.  
normally increase with age [33], and organically reared pigs are usually older at slaughter than pigs from conventional production systems (Table 1).  
Nevertheless, it is imperative to highlight that, as elucidated by the previous research [29], the conditions inherent to extensive production systems, characterized by outdoor access and free-range opportunities, have been found to yield remarkable enhancements in the organoleptic quality of pork. This encompasses a host of desirable attributes, with one noteworthy aspect being the attainment of a vividly more intense reddish hue in comparison to the pork derived from conventional rearing conditions. The greater yellowing of organic meat could be due to the feeding of pigs in the organic system and, in particular, the intake of grass in the free-range system. Organically raised pigs consume a greater amount of vegetable feed containing carotenoid pigments [34; 35]. The fat content is also related to the yellow color of the meat. Our result showed that the meat from organic pigs had the highest values in fat content, which could be the reason for the more yellowish color. The yellowish color of the meat is also due to the high intramuscular lipid content and the incorporation of lipophilic pigments [36].