## 3 Results and Discussion
### Effects of the Pecan Nut Levels on Textural Properties  
The differences found in the textural parameters of the lamb burgers are shown in Table 4. In general, a decrease in Kramer shear force and hardness values was identified due to the addition of different amounts of pecan nuts in their formulation, although this decrease was not significant (\(p\geq 0.05\)). Ayo et al. [42] have indicated that nuts do not affect textural properties and that softer textures are obtained by increasing nut content and therefore decreasing meat content in different meat products. In meat products made from minced meat, such as hamburgers, texture will depend directly on the protein's capacity to create gels or the emulsifying capacity of the non-meat ingredients added [49]. For this reason, the decreasing trend in hardness values can be attributed to the reduced presence of myofibrillar proteins and a diluting effect of non-meat ingredients (pecan nuts) on meat  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multirow{2}{*}{**Control**} & \multicolumn{4}{c}{**With Pecans**} & \multirow{2}{*}{**SEM**} & \multirow{2}{*}{**\(p\)-Value**} \\ \cline{3-3} \cline{5-6}  & & & **5\%** & & **10\%** & & **15\%** \\ \hline pH & 6.06 c & 6.28 b & 6.33 ab & 6.37 a & 0.02 & 0.000 \\ WHC (\%) & 14.85 b & 15.99 ab & 19.31 a & 17.97 ab & 0.56 & 0.014 \\ Colour parameters & & & & & & \\ L* & 48.13 c & 50.38 bc & 52.71 ab & 54.96 a & 0.65 & 0.000 \\ a* & 15.50 a & 13.15 b & 10.50 d & 11.73 c & 0.37 & 0.000 \\ b* & 10.81 c & 12.50 b & 13.05 ab & 14.28 a & 0.28 & 0.000 \\ C* & 18.96 a & 18.18 a & 16.75 b & 18.48 a & 0.23 & 0.001 \\ H\({}^{\text{o}}\) & 34.85 c & 43.54 b & 51.18 a & 50.60 a & 1.28 & 0.000 \\ \hline \hline \end{tabular} a, b, c, d: different letters in the same row indicate significant differences during storage according to Tukey’s HSD test; values are expressed as means. SEM: standard error of the mean; WHC: water-holding capacity.  
\end{table}
Table 2: pH, water-holding capacity and colour properties of raw Merino Lamb burgers with different amounts of pecans in their formulation.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multirow{2}{*}{**Control**} & \multicolumn{4}{c}{**With Pecans**} & \multirow{2}{*}{**SEM**} & \multirow{2}{*}{**\(p\)-Value**} \\ \cline{3-3} \cline{5-6}  & & & **5\%** & & **10\%** & & **15\%** \\ \hline \% Cooking loss & 24.84 b & 28.19 a & 25.00 b & 24.72 b & 0.53 & 0.023 \\ \% Diameter reduction & 16.358 & 18.552 & 16.709 & 16.078 & 1.16 & 0.883 \\ \hline \hline \end{tabular} a, b: different letters in the same row indicate significant differences during storage according to Tukey’s HSD test; values are expressed as means.  
\end{table}
Table 3: Cooking yield of Merino lamb burgers with different amounts of pecans in their formulation.  
protein systems as well as the poorer gelling properties of pecan nut globular proteins at the processing temperature (72 \({}^{\circ}\)C) [34].  
However, the addition of pecan nuts showed significant differences in springiness, cohesiveness, gumminess and chewiness between the control sample and the rest of the samples. In each parameter, the values decreased progressively as the amount of pecan nuts in the formulations increased (\(p<0.05\), \(p<0.001\), \(p<0.05\) and \(p<0.05\), respectively). This may be due to the fact that since all the burgers had the same weight (approx. 100 g), as the % of pecans was increased, the meat amount decreased. Similar trends were reported by Rabadan et al. [50] in lamb burgers made with oils and seeds.