## 3 Results and Discussion
### Carotenoid Profile  
Carotenoids are pigment compounds responsible for the characteristic orange color of carrots. The primary carotenoids identified in the analyzed samples included lutein, zeaxanthin, \(\beta\)-cryptoxanthin, various isomers of \(\beta\)-carotene, and \(\alpha\)-carotene (Table 4). The total carotenoid content in raw carrot was 314.07 \(\upmu\)g/g dw, and this amount increased in all heat-treated samples. The most substantial increases (over 47%) were observed in carrots after boiling and baking, with total carotenoid contents reaching 462.35 and 463.83 \(\upmu\)g/g dw, respectively. In contrast, the sous-vide method had the smallest impact on the total carotenoid content, resulting in an increase of only 16% compared to that of the raw sample. In all carrot samples analyzed, \(\beta\)-carotene was the dominant carotenoid, accounting for 48-59% of the total carotenoid content. In raw carrots, \(\beta\)-carotene was present at 152.29 \(\upmu\)g/g dw, and after heat treatment, its content increased by approximately 25% (steaming in a combi oven) to about 79% (baking). Lutein was the second most abundant carotenoid, although its concentration was more than four times lower than that of \(\beta\)-carotene. Notably, the changes in lutein content due to heat treatment were, in most cases, greater than those observed for \(\beta\)-carotene. The highest lutein content (53.15 \(\upmu\)g/g dw) was found in carrots subjected to steaming in a steel pot. Heat treatment also had a positive effect on the levels of \(\beta\)-cryptoxanthin and 15-\(cis\)-\(\beta\)-carotene, with concentrations ranging from 26.36 to 50.94 \(\upmu\)g/g dw across the samples. In contrast, no significant changes or degradation were observed for zeaxanthin, 13-\(cis\)-\(\beta\)-carotene, or \(\alpha\)-carotene. However, a greater decrease in the content of these carotenoids (approximately 30% from the raw sample) was observed in carrots subjected to boiling and baking.  
Changes in carotenoid content have also been noted by other researchers. For example, [PERSON] and [PERSON] [29] found that cooking had a small but significant effect on these compounds, with boiling increasing the initial carotenoid content by about 15.1%, but steaming caused a slight decrease in them. The cited authors, as in the present study, noted a decrease in a-carotene content and an increase in lutein content due to boiling. An increase in the contents of total carotenoids and \(\beta\)-carotene after boiling and steaming was also shown by [PERSON] and [PERSON] [21] and [PERSON] et al. [28], with the changes being much greater after boiling, which was also confirmed in the present study. In contrast, [PERSON] et al. [4] showed a significantly higher increase in carotenoid content with the sous-vide method than with steaming. [PERSON] et al. [24] and [PERSON] et al. [26] reported that changes in carrots depend not only on the processing method, but also on its duration. In contrast, [PERSON] et al. [30] showed that thermal processing leads to caroten loss, whereas lutein content can be increased by boiling or decreased by baking. Higher carotenoid content in heat-treated carrots is likely the result of the increased release of these compounds from cell structures and their higher extraction with solvent, as temperatures ranging from 65 to 95 \({}^{\circ}\)C disrupt the organelle membrane structure and/or protein-carotenoid interactions [57]. [PERSON] and [PERSON] [58] found that even though cooking heat treatment can have a negative effect on carotenoid content, it has a positive effect on the micellization of caroten and thus increases their bioavailability.