## 3 Results and Discussion
### TBARS, Oxidation-Reduction Potential (ORP), and pH Value
The assessment of the ORP values demonstrated that C and AW samples were characterized by the highest ORP value both after production (347.90 and 341.15 mV) and  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Treatment** & \multicolumn{3}{c}{**Storage Time**} \\ \cline{2-5}  & & **0** & **3 Months** & **8 Months** \\ \hline TBARS & C & 3.76 \(\pm\) 0.08 \({}^{\text{\,{\text{\text@math  
after 8 months of storage (313.00 and 310.50 mV). After 8 months of storage, a significant (\(p<0.05\)) decrease in the redox potential value was noted in all ham samples. The pH values of the beef hams studied during the entire study were in the range of 5.25-6.35 and were typical for raw-ripened meat products [18; 21; 26; 72; 73]. After production, apple vinegar treatment gave a higher pH than both the C and AW treatments. This can be explained by the behavior of the acetic acid bacteria. The concentration of 3-4 g of acetic acid/100 cm\({}^{3}\) in apple vinegar could be the threshold for acetic acid production by the used _Acetobacter_ strains (_Acetobacter pasteurianus_ O4 and _Acetobacter pasteurianus_ MW3). When the threshold is exceeded, some acetic acid bacteria can further oxidize the produced acetic acid to CO\({}_{2}\) and H\({}_{2}\)O\({}_{2}\)[74]. In A treatment, the number of lactic acid bacteria increased with a simultaneous decrease in pH (Tables 2 and 3). During storage, the LAB number also increased in C and AW variants of fermented hams, which resulted in a decrease in pH (Tables 2 and 3). After 8 months of refrigerated storage, a significant decrease in pH was noticed in all ham variants. The lower pH found in the AW and C treatments could have resulted from a higher number of lactic acid bacteria in these variants (Tables 2 and 3). The optimal pH for LAB growth is mildly acidic (5.5-6.0). During fermentation, acid-tolerant LAB produce organic acids such as lactic, acetic, and propionic acid, acidifying raw meat and inhibiting the growth of pathogenic and spoilage bacteria [75]. The most abundant organic acid produced by LAB is lactic acid and, therefore, has a great impact on acidity. The efficiency of lactic acid production is strain-dependent and related to the environmental factors such as temperature, pH, and nutrient availability, i.e., glucose. The end product could be only lactic acid or, in the hetero-fermented pathway, ethanol and CO\({}_{2}\). In comparison to lactic acid, the production of acetic acid by LAB is low, as well as its acidifying effect. But, due to greater non-dissociating proprieties, it could have higher antibacterial activity [75]. The comparison of AW and A beef hams showed that, after production, the TBRAS index was higher in the AW variant (\(p<0.5\)). There were no statistical differences between A and AW after production. After 3 months of storage, A variant was characterized by lower pH (\(p<0.5\)) and, after 8 months, AW had a lower pH (\(p<0.5\)) (Table 1). The observed differences can be explained by the various dynamics of biochemical processes, as well as by the diversity of the bioactive compounds present in acid whey and apple vinegar.