## 3 Results and Discussion
### Total Phenolic and Total Flavonoid Contents  
The content of phenolic compounds in raw carrots was 0.81 mg GAE/g dw (Table 2). [PERSON] et al. [26] determined a higher content of these compounds in carrots, forming 94.74 mg GAE/100 g dw. [PERSON] and [PERSON] [42] reported that the content of phenolic compounds in the carrots they studied was 30.7 mg GAE/g of dry plant material. The content of phenolic compounds in carrots depends on variety, origin [6], climatic conditions [43], farming system [44], type of fertilization (chemical and organic fertilizers) [45], and storage conditions [46]. Heat-treated carrots had a higher concentration of phenolic compounds compared to that of raw carrots. Among the heat-treated samples, sous-vide-cooked carrots had the lowest TPC value (1.01 mg GAE/g dw). This sample was not significantly different from raw carrots. On the other hand, the highest TPC values (1.89 mg GAE/g dw) were determined in carrots cooked by steaming in a steel pot. An increase in phenolic compounds in carrots when cooked in water, steam, and the sous-vide method for 10, 20, and \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Method of Heat Treatment**} & **TPC** & **TFC** \\  & **[mg GAE/g dw]** & **[mg QE/g dw]** \\ \hline Raw sample & 0.81 \(\pm\) 0.06 \({}^{\text{a}}\) & 0.43 \(\pm\) 0.01 \({}^{\text{a}}\) \\ Boiling & 1.75 \(\pm\) 0.10 \({}^{\text{d}}\) & 0.97 \(\pm\) 0.02 \({}^{\text{d}}\) \\ Steaming in steel pot & 1.89 \(\pm\) 0.11 \({}^{\text{d}}\) & 0.83 \(\pm\) 0.01 \({}^{\text{c}}\) \\ Steaming in combi oven & 1.33 \(\pm\) 0.05 \({}^{\text{b}}\) & 0.69 \(\pm\) 0.02 \({}^{\text{b}}\) \\ Baking & 1.68 \(\pm\) 0.09 \({}^{\text{c}}\) & 0.97 \(\pm\) 0.02 \({}^{\text{d}}\) \\ Sous-vide & 1.01 \(\pm\) 0.04 \({}^{\text{a}}\) & 0.93 \(\pm\) 0.02 \({}^{\text{d}}\) \\ \hline \hline \end{tabular} Data are expressed as mean value \(\pm\) standard deviation (\(n=3\)). Values in the same column with different superscript letters are significantly different (\(p\leq 0.05\)).  
\end{table} 
Table 2: Total phenolic compound (TPC) and total flavonoid (TFC) contents of carrot roots before and after different heat treatments. Figure 1: Images of carrot root cross-sections: raw sample (**A**) and processed by boiling (**B**), steaming in steel pot (**C**), steaming in combi oven (**D**), baking (**E**), and sous-vide (**F**). 30 min compared to raw carrots was also observed by [PERSON] et al. [26]. The authors explain this fact by saying that this may have been related to the more severe thermally induced damage to the cell walls and thus more efficient release of phenolic compounds. [PERSON] et al. [47] report that carrots cooked in water, steam, and a microwave contained more phenolic compounds than those of raw carrots. [PERSON] and [PERSON] [21] observed a significant increase in phenolic compounds in carrots subjected to cooking (in water, steam, a microwave, and pressure) and frying, with the greatest increase in the fried and microwaved samples. According to [PERSON] et al. [23], cooking carrots in water had no significant effect on the content of phenolic compounds, while microwave cooking and stir-frying resulted in a significant reduction in the content of these compounds, with stir-fried carrots containing significantly less phenolic compounds than those cooked in water or a microwave. [PERSON] et al. [22] reported that the degradation of phenolic compounds during the sous-vide cooking of carrots ranged from 8.94 to 20.41%, cook-vide from 4.38 to 19.33% (depending on the temperature and duration of the process), and traditional cooking from 16.30 to 22.88% depending on the cooking time. According to [PERSON] et al. [19], cooking in water, microwaving, and frying increased the content of phenolic compounds in carrots. A study by [PERSON] et al.