## 3 Results and Discussion
### Lipid Oxidation
[62] found that cooked hams cured with a lower dose (25 ppm) of sodium nitrite showed significantly higher lipid oxidation after 10 days of storage than the control products cured with a higher dose (100 ppm) of sodium nitrite. Importantly, the groups to which the same amount of nitrite ions were added did not differ significantly (\(p\geq 0.05\)) on any of the analyzed days, regardless of the curing method. Based on our current and previous studies [19; 20; 21], it can be concluded that the use of indirect methods for nitrite production in aqueous, fat-free, or low-fat solutions containing natural buffers may be a more favorable approach than direct nitrite production in meat or meat batters through cold plasma. This is because direct plasma treatment of meat and meat products, as suggested by the studies conducted by [PERSON] [63] or [PERSON] [64], may lead to accelerated lipid oxidation due to the presence of reactive oxygen species in the plasma. Nevertheless, some studies have shown no negative effect of direct plasma treatment on the lipid oxidation of meat products compared to a group without sodium nitrite and plasma treatment [6; 46]. These differences may result from the working gas used and the duration of plasma treatment [2], indicating that further research may be necessary to determine the optimal method for nitrite production in meat products. Figure 2: Fork liver patés in porcelain bowls—top view; from the left: NC—negative control (liver patés without nitrite source); PC1—positive control (liver patés with 60 ppm of sodium nitrite); PTEW1—liver patés with plasma-treated egg white containing 40 NO2–; PC2—(liver patés with 120 ppm of sodium nitrite); PTEW2—liver patés with plasma-treated egg white containing 80 NO2–. \begin{table}
\begin{tabular}{l l c c c c} \hline \hline
**Parameters** & **Group 2,3** & **1 Day** & **3 Day** & **5 Day** & **7 Day** \\ \hline \multirow{4}{*}{TBARS [mg MDA/kg]} & NC & 0.62 \(\pm\) 0.05 & 1.34 \({}^{\mathrm{d}}\)\(\pm\) 0.03 & 1.87 \({}^{\mathrm{c}}\)\(\pm\) 0.03 & 2.06 \({}^{\mathrm{c}}\)\(\pm\) 0.04 \\  & PC1 & 0.58 \(\pm\) 0.04 & 1.12 \({}^{\mathrm{b}}\)\(\pm\) 0.03 & 1.60 \({}^{\mathrm{b}}\)\(\pm\) 0.03 & 1.83 \({}^{\mathrm{b}}\)\(\pm\) 0.02 \\ \cline{1-1}  & PTEW1 & 0.56 \(\pm\) 0.05 & 1.17 \({}^{\mathrm{c}}\)\(\pm\) 0.02 & 1.67 \({}^{\mathrm{b}}\)\(\pm\) 0.06 & 1.86 \({}^{\mathrm{b}}\)\(\pm\) 0.04 \\ \cline{1-1}  & PC2 & 0.49 \(\pm\) 0.04 & 0.88 \({}^{\mathrm{a}}\)\(\pm\) 0.05 & 1.36 \({}^{\mathrm{a}}\)\(\pm\) 0.03 & 1.62 \({}^{\mathrm{a}}\)\(\pm\) 0.03 \\ \cline{1-1}  & PTEW2 & 0.48 \(\pm\) 0.01 & 0.94 \({}^{\mathrm{a}}\)\(\pm\) 0.06 & 1.48 \({}^{\mathrm{a}}\)\(\pm\) 0.02 & 1.59 \({}^{\mathrm{a}}\)\(\pm\) 0.04 \\ \hline \hline \end{tabular}  
* SE—standard error; 2 NC—negative control (liver patés without a nitrite source); PC1—positive control (liver patés with 60 ppm of sodium nitrite); PTEW1—liver patés with plasma-treated egg white containing 40 ppm NO2–; PC2—positive control (liver patés with 120 ppm of sodium nitrite); PTEW2—liver patés with plasma-treated egg white containing 80 ppm NO2–; 3 different superscript lowercase letters within columns (a–d) indicate statistical differences (\(p<0.05\)).  
\end{table} 
Table 5: The effect of plasma-treated egg white on TBARS values (mean \(\pm\) SE 1) of liver patés during storage.