## 4 Discussion
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Temperature (\({}^{\circ}\)C)** & **Time (Day)** & **APC (log CFU/g)** & **LAB (log CFU/g)** & **aw** & **pH** \\ \hline \multirow{6}{*}{4 \({}^{\circ}\)C} & 0 & 5.36 \(\pm\) 0.14 & 0.97 \(\pm\) 0.78 & 0.952 \(\pm\) 0.001 & 6.06 \(\pm\) 0.02 \\  & 3 & 5.28 \(\pm\) 0.34 & 0.54 \(\pm\) 0.77 & 0.940 \(\pm\) 0.006 & 6.08 \(\pm\) 0.01 \\  & 7 & 5.38 \(\pm\) 0.33 & 0.58 \(\pm\) 0.82 & 0.946 \(\pm\) 0.002 & 6.06 \(\pm\) 0.01 \\  & 14 & 5.40 \(\pm\) 0.65 & 0.56 \(\pm\) 0.80 & 0.948 \(\pm\) 0.001 & 6.03 \(\pm\) 0.01 \\  & 21 & 5.36 \(\pm\) 0.40 & 1.12 \(\pm\) 0.97 & 0.946 \(\pm\) 0.002 & 6.08 \(\pm\) 0.01 \\  & 0 & 5.36 \(\pm\) 0.14 & 0.97 \(\pm\) 0.78 & 0.952 \(\pm\) 0.001 & 6.06 \(\pm\) 0.02 \\  & 3 & 5.51 \(\pm\) 0.33 & 0.94 \(\pm\) 0.75 & 0.939 \(\pm\) 0.001 & 6.09 \(\pm\) 0.01 \\
6 \({}^{\circ}\)C & 7 & 5.39 \(\pm\) 0.36 & 1.37 \(\pm\) 0.53 & 0.944 \(\pm\) 0.002 & 6.09 \(\pm\) 0.01 \\  & 14 & 5.63 \(\pm\) 0.33 & 1.98 \(\pm\) 0.15 & 0.949 \(\pm\) 0.004 & 6.02 \(\pm\) 0.02 \\  & 21 & 5.62 \(\pm\) 0.16 & 1.85 \(\pm\) 0.38 & 0.943 \(\pm\) 0.002 & 6.08 \(\pm\) 0.02 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: _Cont._Confirmation of the safety of the tested products when stored at 2 and 4 \({}^{\circ}\)C is provided by data on the maximum growth rate of _L. monocytogenes_ models. It was shown that at 2 and 4 \({}^{\circ}\)C, regardless of whether a low- or high-density suspension was used, the values for _L. monocytogenes_ growth reached negative values, in contrast to bars stored at 6 \({}^{\circ}\)C, where the maximum rates for _L. monocytogenes_ had a value 0.0493 \(\pm\) 0.0303 for LM-2 and 0.0350 \(\pm\) 0.0149 for LM-5. The highest death rate, which corresponds to the lowest maximum rate of _L. monocytogenes_ for LM-5 bars stored at 2 \({}^{\circ}\)C, may mean that the lower the storage temperature and the higher microbial contamination by _L. monocytogenes_, the less favourable the conditions for growth in the tested food matrix. The obtained mean APC counts, \(\mathrm{a_{w}}\), and pH values of the control group are similar to those obtained in previous studies [43]. Our results are characterised by slightly lower numerical variability for the physicochemical factors of RTE meat bars--the lowest \(\mathrm{a_{w}}\) value was 0.939, the highest value was 0.953, and the lowest pH value was 6.02, while the highest value was 6.09. However, our LAB count results for RTE meat bars were lower than those of the previous storage study [43]. The physicochemical properties of the tested bars differ markedly from those of most similar RTE meat bars currently on the market; they usually present lower pH and \(\mathrm{a_{w}}\) values that guarantee the inhibition of most pathogenic and food spoilage microorganisms [55]. Lowering the pH of a product by adding food additives (introducing additional hurdles) helps ensure the microbiological stability of products stored without a temperature regime, making it possible to extend the shelf life (\"hurdle\" technology) [56]. Other studies indicate that, under refrigerated storage conditions, \(\mathrm{a_{w}}\) value has no significant effect on the growth potential of _L. monocytogenes_. Working with different food matrices, it was shown that the only statistically significant effect reducing _L. monocytogenes_ growth potential was the additional use of high-pressure pasteurisation, an alternative non-thermal method of food preservation (HPP) [57]. The pH values of the dried plasma meat bars we tested oscillated between 6.0 and 6.1, while the \(\mathrm{a_{w}}\) value was between 0.94 and 0.95, indicating that the physicochemical properties of this product allow the growth of _L. monocytogenes_[39]. This is consistent with the results of other studies [53], where it was proven that at 4 \({}^{\circ}\)C, the growth of _L. monocytogenes_ was inhibited by the product's acidity at about 5.0 or an \(\mathrm{a_{w}}\) of about 0.96.