## 3 Results and Discussion  
### Physicochemical Properties  
The values of the determined physicochemical properties in chicken patties with different levels of CSS addition are presented in Table 1. The use of CSS in chicken patties significantly affected the pH value (\(p<0.01\)), and lower average pH values were observed in all groups with CSS compared to the control. Among them, the lowest average pH values were determined in the SS2 and SS3 groups, where animal fat was replaced with 4% and 6% CSS, respectively. These results may be due to the addition of CSS, which has a relatively low pH value of 5.34 reported by [PERSON] et al. [2]. Similarly, [PERSON] et al. [34] found that substituting pig-back fat with different levels of germinated wheat fiber in reduced-fat chicken meatballs, and [PERSON] et al. [35] reported that substituting animal fat with cashew apple fiber in chicken meatballs decreased the pH value compared to the control. On the other hand, [PERSON] et al. [29] reported that the addition of up to 3% of CSS did not significantly affect chicken patties' pH value. The cooking process also significantly affected the pH value of chicken patties (\(p<0.01\)). While there was a statistical difference between the average pH values of all groups (control, SS1, SS2, SS3) before and after cooking, the average pH value after cooking was higher (Table 2). \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Control** & **SS1** & **SS2** & **SS3** & **Significance** \\ \hline pH & 6.10 \(\pm\) 0.01 a & 6.02 \(\pm\) 0.03 b & 6.01 \(\pm\) 0.03 c & 6.01 \(\pm\) 0.02 c & **\(\ast\)** \\ Moisture content (\%) & 62.43 \(\pm\) 0.78 a & 61.17 \(\pm\) 0.69 b & 61.44 \(\pm\) 0.52 b & 61.09 \(\pm\) 0.72 c & **\(\ast\)** \\ \(\mathrm{a}_{\mathrm{w}}\) & 0.979 \(\pm\) 0.001 a & 0.976 \(\pm\) 0.001 b & 0.976 \(\pm\) 0.001 b & 0.974 \(\pm\) 0.001 c & **\(\ast\)** \\ TBARS (\(\mu\)mold MDA/kg) & 11.75 \(\pm\) 0.67 d & 18.48 \(\pm\) 0.70 c & 25.91 \(\pm\) 0.47 b & 32.92 \(\pm\) 1.00 a & **\(\ast\)** \\ Moisture retention (\%) & 81.41 \(\pm\) 1.30 b & 85.59 \(\pm\) 1.27 a & 87.34 \(\pm\) 0.58 a & 86.16 \(\pm\) 0.91 a & **\(\ast\)** \\ L* & 72.48 \(\pm\) 3.16 a & 60.27 \(\pm\) 2.10 b & 53.80 \(\pm\) 2.29 c & 50.32 \(\pm\) 1.80 d & **\(\ast\)** \\ Color & a* & 12.50 \(\pm\) 0.52 a & 8.97 \(\pm\) 0.27 b & 7.56 \(\pm\) 0.17 c & 6.46 \(\pm\) 0.20 d & **\(\ast\)** \\ b* & 37.14 \(\pm\) 0.65 a & 26.58 \(\pm\) 0.91 b & 21.64 \(\pm\) 1.31 c & 18.20 \(\pm\) 1.52 d & **\(\ast\)** \\ \hline \hline \end{tabular}  
* Presented values are means \(\pm\) standard error; Control: 12% fat, SS1: 10% fat + 2% silverskin, SS2: 8% fat + 4% silverskin, SS3: 6% fat + 6% silverskin; a–d: Means marked with different letters in the same line are statistically different from each other (\(p<0.05\)); **: \(p<0.01\).  
\end{table} 
Table 1: Physicochemical properties of chicken patties produced with coffee silverskin. 1 \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Before Cooking** & **After Cooking** & **Significance** \\ \hline pH & 5.98 \(\pm\) 0.02 a & 6.09 \(\pm\) 0.01 b & **\(\ast\)** \\ Moisture content (\%) & 63.73 \(\pm\) 0.17 b & 59.34 \(\pm\) 0.16 a & **\(\ast\)** \\ a\({}_{\mathrm{w}}\) & 0.978 \(\pm\) 0.001 b & 0.974 \(\pm\) 0.001 a & **\(\ast\)** \\ TBARS (\(\mu\)mold MDA/kg) & 20.69 \(\pm\) 1.70 a & 23.84 \(\pm\) 1.70 b & **\(\ast\)** \\ L* & 51.69 \(\pm\) 1.55 a & 66.74 \(\pm\) 2.08 b & **\(\ast\)** \\ Color & a* & 9.31 \(\pm\) 0.65 b & 8.43 \(\pm\) 0.33 a & **\(\ast\)** \\ b* & 22.74 \(\pm\) 1.84 a & 29.04 \(\pm\) 1.20 b & **\(\ast\)** \\ \hline \hline \end{tabular}  
* a–b: Means marked with different letters in the same line are statistically different from each other (\(p<0.05\)); **: \(p<0.01\).  
\end{table} 
Table 2: Physicochemical properties of chicken patties at the production stages. This increase in pH is likely due to protein denaturation during cooking which caused imidazolium revelation, the basic R group of the amino acid histidine [36; 37].