## 3 Results and Discussion
### Effect of HP on the Bacterial Growth and the Shelf Life of Sea Bass Fillets
Comparing the growth of TVC under different storage conditions, similar growth rates were obtained in all cases with the exception of 400 MPa, which demonstrated a significant (\(p<0.001\)) increase in the growth rate. Since the growth of the dominant spoilage microorganisms, including the aerobic _Pseudomonas_ spp. and the facultative anaerobic _Brochotthrix thermosphacta_, is promoted in aerobic conditions, as expected, the \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Fish Fillet Treatment** & **Growth Rate (d\({}^{-1}\))** & **Lag Phase (d)** & **R-Square** & **Shelf Life * (d)** \\ \hline Untreated fillet & 0.432 d (\(\pm\)0.019) & 3.9 bc (\(\pm\)0.3) & _0.999_ & 10 a (\(\pm\)0.1) \\ Untreated fillet (aerobically stored) & 0.301 abc (\(\pm\)0.031) & 0.1 a (\(\pm\)0.0) & _0.992_ & 10 a (\(\pm\)0.8) \\ \hline
100 MPa\_3 \({}^{\circ}\)C\_5 min & 0.459 3 (\(\pm\)0.036) & 3.3 2 (\(\pm\)0.5) & _0.997_ & 11 1 (\(\pm\)0.0) \\
200 MPa\_3 \({}^{\circ}\)C\_5 min & 0.439 3 (\(\pm\)0.052) & 3.3 2 (\(\pm\)0.8) & _0.993_ & 13 12 (\(\pm\)0.1) \\
300 MPa\_3 \({}^{\circ}\)C\_5 min & 0.401 3 (\(\pm\)0.035) & 2.7 2 (\(\pm\)0.8) & _0.994_ & 15 23 (\(\pm\)0.1) \\
400 MPa\_3 \({}^{\circ}\)C\_5 min & 0.218 2 (\(\pm\)0.021) & 9.8 3 (\(\pm\)0.2) & _0.990_ & 32 6 (\(\pm\)2.3) \\ \hline
100 MPa\_3 \({}^{\circ}\)C\_10 min & 0.153 AB,12 (\(\pm\)0.025) & 0.0 A,1 (\(\pm\)0.0) & _0.924_ & 15 BC,34 (\(\pm\)2.3) \\
200 MPa\_3 \({}^{\circ}\)C\_10 min & 0.212 BC,2 (\(\pm\)0.021) & 0.0 A,1 (\(\pm\)0.0) & _0.974_ & 17 C,4 (\(\pm\)1.6) \\
300 MPa\_3 \({}^{\circ}\)C\_10 min & 0.435 F3 (\(\pm\)0.065) & 12 FC,4 (\(\pm\)1.2) & _0.952_ & 23 E,5 (\(\pm\)0.3) \\
400 MPa\_3 \({}^{\circ}\)C\_10 min & 0.144 AB,1 (\(\pm\)0.011) & 14 C,4 (\(\pm\)2.8) & _0.990_ & 50 C,6 (\(\pm\)0.2) \\ \hline
100 MPa\_7 \({}^{\circ}\)C\_10 min & 0.192 ABC (\(\pm\)0.012) & 1.7 AB (\(\pm\)0.6) & _0.996_ & 11 A (\(\pm\)0.1) \\
200 MPa\_7 \({}^{\circ}\)C\_10 min & 0.270 CD (\(\pm\)0.053) & 0.1 A (\(\pm\)0.0) & _0.960_ & 14 B (\(\pm\)2.5) \\
300 MPa\_7 \({}^{\circ}\)C\_10 min & 0.212 BC (\(\pm\)0.024) & 3.7 BC (\(\pm\)1.9) & _0.980_ & 21 D (\(\pm\)0.2) \\
400 MPa\_7 \({}^{\circ}\)C\_10 min & 0.114 A (\(\pm\)0.006) & 22 H (\(\pm\)2.3) & _0.992_ & 67 H (\(\pm\)0.1) \\ \hline
100 MPa\_25 \({}^{\circ}\)C\_10 min & 0.408 d,EF (\(\pm\)0.075) & 5.4 cd,CD (\(\pm\)0.9) & _0.980_ & 11 b,A (\(\pm\)0.1) \\
200 MPa\_25 \({}^{\circ}\)C\_10 min & 0.353 bed,E (\(\pm\)0.087) & 9.9 EEF (\(\pm\)0.5) & _0.928_ & 20 e,D (\(\pm\)1.7) \\
300 MPa\_25 \({}^{\circ}\)C\_10 min & 0.334 bed,CD (\(\pm\)0.050) & 7.9 e,DE (\(\pm\)1.8) & _0.983_ & 22 e,DE (\(\pm\)0.2) \\
400 MPa\_25 \({}^{\circ}\)C\_10 min & 0.217 a,BC (\(\pm\)0.021) & 13 b (\(\pm\)2.4) & _0.977_ & 37 b,F (\(\pm\)0.3) \\ \hline \hline \end{tabular}  
* Estimated considering limit of acceptability of 7 log CFU/g. Values are means \(\pm\) standard error of regression. Different lowercase letters in the same column indicate significant difference (\(p<0.05\)) between tested samples, according to [PERSON]’s mean values post hoc comparison test in terms of applied pressure and storage conditions. Different uppercase letters in the same column indicate significant difference in terms of applied pressure and temperature, and different numbers in the same column indicate significant difference in terms of applied pressure and processing time.  
\end{table} 
Table 2: Estimated microbial growth parameters and shelf life of untreated and HP-treated vacuum-packed sea bass fillets based on TVC values as the dominant spoilage microflora. shelf life of samples stored aerobically was significantly lower than the corresponding shelf life of samples stored in a vacuum, particularly for samples treated at 200-400 MPa. Regarding the effect of processing time on the growth of TVC, as presented in Table 2, the highest estimated shelf life was obtained for samples treated for 10 min.