## Results and Discussion
### Kinetics of Microbiological Data and Model Development/Validation
The recorded values of \(E_{a}\) in controls were close to the ones reported in previous studies. Specifically, the reported range of \(E_{a}\) ranged from 73.2 to 91.9 kJ/mol for _B. thermosphacta_, while from 92.8 to 99.6 kJ/mol for LAB during storage of ground beef and/or pork under MAP or aerobic conditions [37; 38; 39]. Goodness-of-fit indices (R\({}^{2}\) and RMSE) indicated that both secondary models adequately described the microbial growth data (Table 2). A good agreement between fitted and observed values of _B. thermosphacta_ on controls and \"_tsipouro_\" was observed, since A\(\!f\) and B\(\!f\) were close to 1, both with square root model (_Af_: 1.05-1.09; B\(\!f\): 0.94-0.99) or Arrhenius equation (_Af_: 1.07-1. 11; B\(\!f\): 0.92-0.96) [29] (Figure 41a,l,b). The latter is also enforced by the fact that the pRE indices on controls (1.000) and \"_tsipouro_\" samples (1.000), met the criterion of pRE \(\geq\) 0.70 for both models tested [32]. In case of LAB, both models tend to constantly (but not substantially) underestimate their growth, thus resulting in pRE ranging from 0.714 to 1.000 regardless of model tested (Figure 41 \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Parameters**} & \multicolumn{4}{c}{_B. thermosphacta_} & \multicolumn{2}{c}{**LAB**} \\ \cline{2-7}  & \multicolumn{2}{c}{**Control**} & \multicolumn{2}{c}{**“_tsipouro_”} & \multicolumn{2}{c}{**Control**} & \multicolumn{2}{c}{**“_tsipouro_”} \\ \cline{2-7}
**Indices** & **Estimate** & _p_**-Value** & **Estimate** & _p_**-Value** & **Estimate** & _p_**-Value** & **Estimate** & _p_**-Value** \\ \hline \multicolumn{7}{c}{**Square Root Model**} \\ \(b\) & 0.054 \(\pm\) 0.005 & 0.000 & 0.059 \(\pm\) 0.006 & 0.000 & 0.059 \(\pm\) 0.008 & 0.000 & 0.063 \(\pm\) 0.009 & 0.000 \\ \(T_{0}\) (C) & \(-\)11.3 \(\pm\) 1.6 & 0.000 & \(-\)6.2 \(\pm\) 1.2 & 0.000 & \(-\)7.8 \(\pm\) 1.3 & 0.000 & \(-\)4.9 \(\pm\) 1.6 & 0.000 \\ R\({}^{2}\) & 0.865 & & 0.782 & & 0.805 & & 0.760 \\ RMSE & 0.017 & & 0.016 & & & 0.019 & & 0.029 \\ \hline \multicolumn{7}{c}{**Arhenius Model**} \\ \(E_{a}\) (J/mol) & 90.2 \(\pm\) 12.2 & 0.000 & 87.2 \(\pm\) 17.1 & 0.002 & 92.8 \(\pm\) 10.4 & 0.000 & 124.8 \(\pm\) 15.0 & 0.000 \\ \(\ln k_{\rm{\tiny{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{\rm{      {\rm{            }}}}}}}}}}}}}}\) (day^{-1}) & \(-\)0.586 \(\pm\) 0.092 & 0.001 & \(-\)1.167 \(\pm\) 0.129 & 0.000 & \(-\)0.833 \(\pm\) 0.081 & 0.000 & \(-\)1.448 \(\pm\) 0.113 & 0.000 \\ R\({}^{2}\) & 0.901 & & 0.813 & & 0.859 & & 0.831 & \\ RMSE & 0.057 & & 0.111 & & 0.082 & & 0.173 & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Estimated parameters and statistics of the developed secondary square root growth models and Arrhenius models of _B. thermosphacta_ and LAB on ground beef (500 \(g\)) packaged with absorbent cloths supplemented with 50 mL of \"_tsipouro_\" (40 mL under the ground beef piece and 10 mL under the labelling, facing the headspace) and stored at 0, 4, 8, and 12 \({}^{\circ}\)C under 80% O\({}_{2}\): 20% O\({}_{2}\). Untreated samples served as controls. comparing the two models studied, square root model showed slightly better performance compared to Arrhenius, regardless of microorganism and treatment.