## 3 Results and Discussion
### Fatty Acid Analysis of Beef Burgers  
The lipid profile of the control and reformulated burgers is presented in Table 3. As expected, appreciable changes in the lipid profile were observed due to the 50% reformulation of the fat content of the beef burgers. A tendency for a reduction in SFA content was observed, mainly due to a significant change (\(p<0.05\)) in certain saturated fatty acids (C13:0, C15:0, and C19:0), as well as a non-significant reduction for C18:0. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **CB** & **FRB** & **FRB-AE** & **FRB-TAE** \\ \hline C4:0 & 0.29 \(\pm\) 0.01 a & 0.22 \(\pm\) 0.03 a & 0.17 \(\pm\) 0.03 a & 0.10 \(\pm\) 0.13 a \\ C10:0 & 0.07 \(\pm\) 0.00 a & 0.06 \(\pm\) 0.01 a & 0.07 \(\pm\) 0.04 a & 0.07 \(\pm\) 0.01 a \\ C12:0 & 0.25 \(\pm\) 0.01 a & 0.19 \(\pm\) 0.02 a & 0.19 \(\pm\) 0.08 a & 0.20 \(\pm\) 0.04 a \\ C13:0 & 0.07 \(\pm\) 0.00 a & 0.06 \(\pm\) 0.01 a & 0.01 \(\pm\) 0.01 b & 0.04 \(\pm\) 0.01 ab \\ C14:0 & 9.47 \(\pm\) 0.04 a & 8.35 \(\pm\) 0.33 a & 8.37 \(\pm\) 2.37 a & 8.43 \(\pm\) 1.09 a \\ C15:0 & 1.14 \(\pm\) 0.03 a & 0.94 \(\pm\) 0.09 ab & 0.75 \(\pm\) 0.11 b & 0.86 \(\pm\) 0.05 ab \\ C16:0 & 27.08 \(\pm\) 0.16 a & 25.95 \(\pm\) 1.24 a & 28.06 \(\pm\) 3.33 a & 28.28 \(\pm\) 2.40 a \\ C17:0 & 2.25 \(\pm\) 0.08 a & 1.79 \(\pm\) 0.16 ab & 1.23 \(\pm\) 0.22 b & 1.52 \(\pm\) 0.13 b \\ C18:0 & 15.54 \(\pm\) 0.73 a & 12.2 \(\pm\) 1.81 a & 8.59 \(\pm\) 2.60 a & 11.33 \(\pm\) 1.33 a \\ C19:0 & 0.10 \(\pm\) 0.01 a & 0.07 \(\pm\) 0.01 ab & 0.02 \(\pm\) 0.02 b & 0.02 \(\pm\) 0.03 b \\ C20:0 & 0.12 \(\pm\) 0.01 a & 0.16 \(\pm\) 0.02 a & 0.14 \(\pm\) 0.06 a & 0.14 \(\pm\) 0.05 a \\ SFA & 56.38 \(\pm\) 1.01 a & 99.7 \(\pm\) 3.68 a & 47.58 \(\pm\) 3.03 a & 50.99 \(\pm\) 1.89 a \\ C14:In-5 & 0.08 \(\pm\) 0.00 a & 0.08 \(\pm\) 0.01 b & 0.02 \(\pm\) 0.02 b & 0.02 \(\pm\) 0.02 b \\ C16:In-5 & 0.11 \(\pm\) 0.00 a & 0.08 \(\pm\) 0.00 a & 0.03 \(\pm\) 0.04 a & 0.04 \(\pm\) 0.05 a \\ C16:In-7 & 6.38 \(\pm\) 0.43 a & 6.77 \(\pm\) 0.48 a & 6.80 \(\pm\) 0.88 a & 5.77 \(\pm\) 0.03 a \\ C16:In-9 & 0.27 \(\pm\) 0.01 a & 0.27 \(\pm\) 0.00 a & 0.24 \(\pm\) 0.03 a & 0.25 \(\pm\) 0.01 a \\ C17:In-7 & 1.18 \(\pm\) 0.04 a & 1.14 \(\pm\) 0.05 ab & 0.94 \(\pm\) 0.06 ab & 0.91 \(\pm\) 0.08 b \\ C18:In-7 & 1.28 \(\pm\) 0.05 a & 1.12 \(\pm\) 0.03 ab & 0.76 \(\pm\) 0.21 b & 0.95 \(\pm\) 0.02 ab \\ C18:In-9 & 29.95 \(\pm\) 0.50 b & 34.70 \(\pm\) 2.30 ab & 37.30 \(\pm\) 2.79 a & 35.21 \(\pm\) 1.22 ab \\ C19:In-9 & 0.15 \(\pm\) 0.00 a & 0.13 \(\pm\) 0.01 a & 0.05 \(\pm\) 0.07 a & 0.04 \(\pm\) 0.06 a \\ C20:In-7 & 0.14 \(\pm\) 0.01 a & 0.14 \(\pm\) 0.01 a & 0.08 \(\pm\) 0.11 a & 0.12 \(\pm\) 0.04 a \\ C20:In-9 & 0.15 \(\pm\) 0.04 a & 0.1 \(\pm\) 0.01 a & 0.09 \(\pm\) 0.02 a & 0.07 \(\pm\) 0.02 a \\ MUFA & 39.72 \(\pm\) 0.99 a & 44.53 \(\pm\) 2.83 a & 46.29 \(\pm\) 2.38 a & 43.36 \(\pm\) 1.53 a \\
9c,11t-C18:2 & 0.36 \(\pm\) 0.01 a & 0.32 \(\pm\) 0.01 a & 0.16 \(\pm\) 0.08 a & 0.18 \(\pm\) 0.08 a \\ C18:2n-6 & 2.46 \(\pm\) 0.04 b & 4.06 \(\pm\) 0.74 ab & 4.75 \(\pm\) 0.57 a & 4.23 \(\pm\) 0.15 ab \\ C20:2n-6 & 0.09 \(\pm\) 0.00 a & 0.05 \(\pm\) 0.00 ab & 0.01 \(\pm\) 0.01 b & 0.02 \(\pm\) 0.02 b \\ C20:3n-6 & 0.12 \(\pm\) 0.01 a & 0.12 \(\pm\) 0.02 a & 0.09 \(\pm\) 0.05 a & 0.11 \(\pm\) 0.02 a \\ C20:4n-6 & 0.31 \(\pm\) 0.03 a & 0.29 \(\pm\) 0.03 a & 0.28 \(\pm\) 0.13 a & 0.31 \(\pm\) 0.06 a \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Fatty acid composition of beef burgers (g/100 g of total fatty acids). Regarding MUFA content, a significant increase (\(p<0.05\)) in oleic acid (C18:1n-9) was observed, ranging from 43.36-46.29 g/100 g for fat-replaced burgers. Oleic acid is the main fatty acid present in EVOO, constituting approximately 55-83% of total fatty acids [14]; therefore, an increase in FRBs was anticipated. Ozturk-Kerimoglu et al. [48] reported similar results when partially replacing fat with olive oil in model meat batters, achieving an increase in oleic acid from 40.13 to 50.97%. PUFA content was also altered due to reformulation with EVOO.