## 3 Results and Discussions
### Evaluation of the Nutrient Content of the Analyzed Fish Dishes
#### 3.1.1 Evaluation of Processing Losses of the Analyzed Products  
Food loss and waste, including cooking loss, are crucial factors that influence the catering sector because they can generate financial losses, depending on the selected cooking process [42]. Cooking loss is of special interest in the catering sector because of the changes in the shape, color, and texture of the product [43; 44]. Cooking loss is defined as a mixture of liquids and solids removed from the fish during cooking and depends on several factors: humidity, pressure, temperature and cooking time, ventilation and the heat distribution system, muscle fiber composition, and connective tissue [45]. Cooking losses are calculated based on the weight of the fish sample before and after heat treatment, as water comes out of the product in the form of vapor and liquid [46]. %Cooking loss = 100 \(\times\) (W1 \(-\) W2)/W1, where W1 is represented by the initial weight of the samples before cooking and W2 is the weight of the cooked samples [47]. In the case of the cook-serve production system, the highest quantitative losses were recorded for sample A2 (microwave cooking, 28.55 \(\pm\) 1.23%) and sample A3 (convective cooking, 30.91 \(\pm\) 2.01%), results that are not significantly different (\(p\) > 0.05). The lowest rate of cooking loss was observed in the sous vide system (14.25 \(\pm\) 1.57%), which is represented by the liquid extracted from the product through the vacuum created in the special packaging bag. This result was found to be significantly different as compared to all of the other samples (\(p\) < 0.05). Through the water removed from the product, in the liquid state, significant amounts of lipids and fat-soluble compounds, soluble proteins, vitamins, minerals, etc., are lost, with the possibility of reintegrating this by-product into other culinary preparations. The two-stage cooling applied to sample A4 (CC-CC) resulted in a cooking loss of 35.68 \(\pm\) 2.32%, and the three-stage cooling applied to sample A5 (CC-CF) with a temperature of \(-\)18 \({}^{\circ}\)C  
\begin{table}
\begin{tabular}{c c c c c c c} \hline  & **A0** & **A1** & **A2** & **A3** & **A4** & **A5** \\ \hline Content loss, \% & - & 14.25 \(\pm\) 1.57 \({}^{\mathrm{a}}\) & 30.91 \(\pm\) 2.01 \({}^{\mathrm{b}}\) & 28.55 \(\pm\) 1.23 \({}^{\mathrm{b}}\) & 35.68 \(\pm\) 2.32 \({}^{\mathrm{c}}\) & 40.25 \(\pm\) 1.57 \({}^{\mathrm{d}}\) \\ \hline Dry substance, \% & 30.98 \(\pm\) 0.02 \({}^{\mathrm{a}}\) & 31.84 \(\pm\) 0.04 \({}^{\mathrm{a}}\) & 31.47 \(\pm\) 0.38 \({}^{\mathrm{a}}\) & 31.40 \(\pm\) 0.08 \({}^{\mathrm{a}}\) & 33.57 \(\pm\) 0.04 \({}^{\mathrm{b}}\) & 33.86 \(\pm\) 0.04 \({}^{\mathrm{b}}\) \\ \hline Proteins, \% & 14.32 \(\pm\) 0.02 \({}^{\mathrm{a}}\) & 15.22 \(\pm\) 0.09 \({}^{\mathrm{a}}\) & 16.66 \(\pm\) 0.12 \({}^{\mathrm{b}}\) & 15.90 \(\pm\) 0.16 \({}^{\mathrm{a}}\) & 16.93 \(\pm\) 0.21 \({}^{\mathrm{c}}\) & 17.36 \(\pm\) 0.03 \({}^{\mathrm{c}}\) \\ \hline Insoluble proteins, \% & 4.37 \(\pm\) 0.01 \({}^{\mathrm{a}}\) & 1.53 \(\pm\) 0.05 \({}^{\mathrm{b}}\) & 1.53 \(\pm\) 0.05 \({}^{\mathrm{b}}\) & 1.78 \(\pm\) 0.02 \({}^{\mathrm{c}}\) & 2.15 \(\pm\) 0.04 \({}^{\mathrm{c}}\) & 1.58 \(\pm\) 0.02 \({}^{\mathrm{b}}\) \\ \hline Digestibility, \% & 69.51 \({}^{\mathrm{a}}\) & 89.91 & 89.91 \(\pm\) 0.03 \({}^{\mathrm{c}}\) & 89.31 \(\pm\) 0.20 \({}^{\mathrm{c}}\) & 86.48 \(\pm\) 0.11 \({}^{\mathrm{b}}\) & 90.67 \(\pm\) 0.21 \({}^{\mathrm{c}}\) \\ \hline Carbohydrates, \% & 0.73 \(\pm\) 0.02 \({}^{\mathrm{a}}\) & 1.10 \(\pm\) 0.04 \({}^{\mathrm{b}}\) & 1.05 \(\pm\) 0.04 \({}^{\mathrm{b}}\) & 1.93 \(\pm\) 0.05 \({}^{\mathrm{c}}\) & 1.23 \(\pm\) 0.05 \({}^{\mathrm{b  
resulted in a cooking loss of 40.25 \(\pm\) 1.57%. Moisture losses individualize production yields and specific raw material consumption with a direct impact on economic efficiency.