## 3 Results and Discussion
### Oxidation-Reduction Potential and TBARS Index  
The ramifications of oxidation are a primary factor contributing to consumer aversion toward these products, as it significantly diminishes their sensory quality and shelf life, while also giving rise to potentially harmful byproducts [40]. The effectiveness of various food preservation techniques, as well as the effects of processing on the overall quality and safety of food, can be better understood through the analysis of secondary compounds produced during these processes. One important measure in this analysis is the TBARS (thiobarbituric acid reactive substances) value, which serves as a key indicator of lipid oxidation levels within food products. Elevated TBARS values are often linked to an increase in off-flavor intensity, suggesting that as foods undergo lipid oxidation, they may develop undesirable flavors that can affect consumer acceptability [41]. The analysis of TBARS shows that the addition of selected strains of \(G\). _oxydans_ in the fermented sausage significantly reduces oxidative processes in meat (Table 4). The TBARS test, which measures lipid peroxidation and thus oxidative reactivity, indicated that formulations with O1 and O2 had lower values compared to the control C, which exhibited the highest TBARS concentration; nevertheless, these values were higher than those of the cured sample. During processing, the levels of TBARS may decrease in the product, likely due to the binding of malondialdehydedehyde (MDA) to amino acids produced by proteolytic reactions. This binding occurs through the formation of covalent linkages, either via Schiff base formation or through nitrite residues, as MDA can undergo nitrosation reactions [42]. This phenomenon was observed in the control samples C, O1, and O2 in this study. \(G\). _oxydans_ strains possess the capability to limit oxidative changes in fermented sausages; however, their effectiveness is not comparable to that of nitrites. The oxidation-reduction potential (ORP) values represent the capacity of a biochemical system to either accept or donate electrons in chemical reactions. A lower redox potential \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Parameter**} & \multirow{2}{*}{**Time**} & \multicolumn{4}{c}{**Treatment**} \\ \cline{3-6}  & & **C** & **P** & **O1** & **O2** \\ \hline \multirow{3}{*}{TBARS (mg MDA/kg of product)} & 0 & 0.91 \(\pm\) 0.01 \({}^{\text{aC}}\) & 0.60 \(\pm\) 0.02 \({}^{\text{aA}}\) & 0.80 \(\pm\) 0.01 \({}^{\text{bB}}\) & 0.80 \(\pm\) 0.01 \({}^{\text{bB}}\) \\  & 1 & 0.89 \(\pm\) 0.01 \({}^{\text{aD}}\) & 0.64 \(\pm\) 0.01 \({}^{\text{bA}}\) & 0.78 \(\pm\) 0.01 \({}^{\text{aC}}\) & 0.73 \(\pm\) 0.01 \({}^{\text{aB}}\) \\ \hline \multirow{3}{*}{ORP (mV)} & 0 & 449.97 \(\pm\) 5.71 \({}^{\text{aC}}\) & 468.57 \(\pm\) 1.18 \({}^{\text{bD}}\) & 436.10 \(\pm\) 1.85 \({}^{\text{aB}}\) & 417.67 \(\pm\) 0.74 \({}^{\text{aA}}\) \\  & 1 & 460.97 \(\pm\) 1.35 \({}^{\text{aC}}\) & 463.80 \(\pm\) 0.86 \({}^{\text{aC}}\) & 441.53 \(\pm\) 2.93 \({}^{\text{aB}}\) & 431.30 \(\pm\) 0.91 \({}^{\text{bA}}\) \\ \hline \hline \end{tabular}  
* The values are expressed as means \(\pm\) standard deviations; \({}^{\text{aD}}\) the means marked with lowercase letters differ significantly between times (\(p<0.05\)); \({}^{\text{aD},\text{C},\text{D}}\) means marked with uppercase letters differ significantly between treatments (\(p<0.05\)).  
\end{table} 
Table 4: The values of oxidation–reduction potential and TBARS index of sausage during storage. indicates a higher tendency for electron donation, which plays a crucial role in neutralizing free radicals that can cause cellular damage. Consequently, ORP can be a valuable indicator of the presence of ingredients with antioxidant characteristics, which help protect against oxidative stress. The lowest ORP value was recorded in the O1 and O2 treatment at 436.10 mV and 417.67 mV, respectively.