## 3 Results and Discussion
### Textural Parameters  
The textural parameter values of fish burgers are shown in Table 3.  
Compared to control carp burgers, the addition of 1% _Isochryssi galbana_, 1% _Picochlorum_ sp., or 1% _Chlorella minutissima_ led to a significant increase in hardness. This could presumably be attributed to the compositional differences between control and microalgae-fortified burgers, resulting in different protein, fat, and water ratios, important elements in determining the final product consistency [27]. These results are in accordance with reports by [PERSON] et al. [27] and [PERSON] et al. [28] on \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & **Control** & **0.5\%** & **1\%** & **0.8\%** & **1\%** & **0.9\%** & **1\%** \\  & **Burger** & **Isochryssi** & **Isochryssi** & **Picochlorum** & **Picochlorum** & **Chlorella** & **Chlorella** \\  & **Burger** & **Burger** & **Burger** & **Burger** & **Burger** & **Burger** \\ \hline pH & 7.21 \(\pm\) 0.07 & 7.175 \(\pm\) 0.005 & 7.17 \(\pm\) 0.001 & 7.185 \(\pm\) 0.005 & 7.17 \(\pm\) 0.01 & 7.17 \(\pm\) 0.01 & 7.16 \(\pm\) 0.001 \\ Water activity (an) & 0.982 \(\pm\) 0.00 & 0.981 \(\pm\) 0.001 & 0.88 \(\pm\) 0.001 & 0.98 \(\pm\) 0.001 & 0.971 \(\pm\) 0.0004 & 0.982 \(\pm\) 0.001 & 0.972 \(\pm\) 0.001 \({}^{\text{ad}}\) \\ Moisture (\% FW) & 77.03 \(\pm\) 0.055 & 7.682 \(\pm\) 0.002* & 7.66 \(\pm\) 0.106* & 7.67 \(\pm\) 0.3 & 7.665 \(\pm\) 0.03* & 7.675 \(\pm\) 0.19* & 7.65 \(\pm\) 0.15* \\ Total solids (\% FW) & 22.96 \(\pm\) 0.06 & 23.18 \(\pm\) 0.08 & 23.31 \(\pm\) 0.16* & 23.3 \(\pm\) 0.03* & 23.35 \(\pm\) 0.03* & 23.24 \(\pm\) 0.19 & 23.5 \(\pm\) 0.145* \\ Proteins (\% DW) & 79.66 \(\pm\) 0.12 & 79.44 \(\pm\) 0.04 & 79.15 \(\pm\) 0.05 & 79.36 \(\pm\) 0.042 & 79.5 \(\pm\) 0.355 & 79.15 \(\pm\) 0.650 & 79.20 \(\pm\) 0.055 \\ Fats (\% DW) & 7.8\(\pm\) 0.15 & 7.71 \(\pm\) 0.14 & 7.65 \(\pm\) 0.120 & 7.65 \(\pm\) 0.225 & 7.55 \(\pm\) 0.26* & 7.20 \(\pm\) 0.15 & 7.64 \(\pm\) 0.1 \\ Ash C-DW & 11.13 \(\pm\) 0.11 & 11.29 \(\pm\) 0.06 & 11.77 \(\pm\) 0.07* & 11.33 \(\pm\) 0.02* & 11.9 \(\pm\) 0.101* & 11.29 \(\pm\) 0.05 & 11.49 \(\pm\) 0.03* \\ Carbohydrates (\% DW) & 2.8 \(\pm\) 0.15 & 2.8 \(\pm\) 0.12 & 2.82 \(\pm\) 0.13 & 2.8 \(\pm\) 0.1 & 2.89 \(\pm\) 0.17 & 2.81 \(\pm\) 0.2 & 2.84 \(\pm\) 0.17 \\ Total dietary fibers & 0.329 \(\pm\) 0.025 & 0.575 \(\pm\) 0.06 & 0.49 \(\pm\) 0.05* & 0.47 \(\pm\) 0.07* & 0.86 \(\pm\) 0.12* & 0.46 \(\pm\) 0.06* & 0.674 (0.05)* \\ \hline Control vs. fortified (0.5, 1, and 1.5\%) burgers: \({}^{\text{a}}\)\(p<0.05\); \({}^{\text{b}}\)\(p<0.01\); \({}^{\text{c}}\)\(p<0.001\). & 0.5\% microalgae burgers vs. 1 and 1.5\% microalgae burgers: \({}^{\text{d}}\)\(p<0.05\); \({}^{\text{e}}\)\(p<0.01\); \({}^{\text{f}}\)\(p<0.001\). The percentage is calculated relative to a dry weight basis (DW) for proteins, fats, Ash, carbohydrates and total dietary fibers whereas the moisture content and total solids are expressed with respect to a fresh weight basis (FW). & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Mean values for physicochemical characteristics of control and microalgae-fortified burgers at one week after production. burger patties with added seaweeds. Furthermore, fibers and polysaccharides of microalgae can play an important role in modifying the hardness of these processed products. Indeed, depending on the amount and type of fibers, varying results were reported regarding the hardness of food products. Thus, both hardening and softening have been observed when fibers were added to various cooked food products [19; 29]. In addition, chewiness reflected results pertaining to hardness, and these results were not surprising since chewiness is a secondary parameter that depends on hardness [30]. However, the addition of microalgae had no significant effect on the springiness and cohesiveness of carp burgers (Table 3). Cohesiveness results of carp burgers formulated with 1% of microalgae were comparable with the values reported by [PERSON] et al.