## 4 Conclusions  
In summary, this study demonstrated the different effects of thermal processing methods (boiling in water, steaming in a pot, steaming in a combi oven, baking, and sous-vide cooking) on the color, phenolic compound content and profile, carotenoid profile, and antioxidant capacity of whole carrot roots. Regardless of the processing method applied to carrot roots, an increase in the content of bioactive compounds and antioxidant capacity (measured by DPPH and ABTS assays) was found. The sous-vide technique resulted in the smallest changes in phenolic compound and carotenoid contents, as well as antioxidant capacity, compared to those of raw carrot roots. However, significant losses of specific phenolic compounds (vanillic acid and rutin) and carotenoids (\(\alpha\)-carotene, zeaxanthin, and 13-\(cis\)-\(\beta\)-carotene) were observed after processing.  
This study provides valuable insights for both industrial processors and consumers, enabling informed choices to balance carrot quality with practical processing and cooking considerations. The results indicate that heat treatment of whole, unpeeled roots using traditional techniques, such as boiling or baking, significantly enhances the release of phenolic compounds and carotenoids, which positively impact the antioxidant capacity of processed carrots. This presents an opportunity for producers to improve the nutritional value of carrot-based products. While many researchers highlight the advantages of the sous-vide technique over traditional cooking methods, our study demonstrated that steaming in the oven may be a more attractive option for consumers. This method not only improves the bioavailability of bioactive compounds (particularly phenolic compounds) to a greater extent than sous-vide but also minimally alters the characteristic orange hue of carrots compared to all the other heat treatments applied.  
Future research could expand on these findings by investigating the effects of different pre-treatment methods for carrots, such as peeling versus non-peeling, slicing versus whole processing, and variations in slicing techniques. Such investigations could provide valuable insight into how surface exposure, internal structure, and tissue integrity influence the retention or degradation of key nutrients, antioxidants, and other bioactive compounds during heat treatment. Moreover, the role of processing parameters, including cooking time, temperature, and their interactions with pre-treatment methods, warrants further exploration. For example, studies could examine how variations in sous-vide temperature or steaming time affect bioactive compound profiles and sensory characteristics. Investigating the combined effects of pre-treatment and specific cooking techniques on nutrient retention, antioxidant capacity, and sensory properties may facilitate the optimization of thermal processing to preserve the nutritional value and health-promoting properties of carrots.  
Conceptualization, A.N.; methodology, A.N., T.S., B.P. and M.T.; formal analysis, A.N., T.S., B.P. and M.T.; investigation, A.N., T.S., B.P. and M.T.; resources, A.N.; data curation, A.N., T.S. and M.T.; writing--original draft preparation, A.N., T.S., B.P. and M.T.; writing--review and editing, A.N. and M.T.; visualization, A.N. and M.T.; supervision, A.N. and T.S.; project administration, A.N.; funding acquisition, A.N. and T.S. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors declare no conflicts of interest.