## 3 Results
### Effect of VI on the Chemical Composition of the Products  
A typical carotenoid profile was identified in the tested cultivars [43]. The Baltimore cultivar was characterized by a higher content of these compounds (Table 3). However, vacuum impregnation caused a significant decrease in carotenoids in this cultivar, regardless of the applied pressure. The conducted research may indicate that carotenoid content in impregnated carrot slices is influenced more by cultivar characteristics than impregnation conditions. The decrease in carotenoid content in the Baltimore F1 cultivar may be associated with degradation as a result of oxidation or a slight outflow of carotenoids to the solution from tissue damaged by cutting or impregnation. A study by [PERSON] et al. [44] showed that soaking carrot flakes in a solution of ascorbic and citric acid may have a protective effect in relation to carotenoids. No such effect was noted as a result of impregnation. This may be due to different degrees of tissue fragmentation (flakes versus slices), which, on the one hand, may intensify degradation processes, while on the other hand, may improve the effectiveness of ascorbic acid. Komaro cultivar carrot slices contained a significantly higher lignin and pectin content (Table 2), which could have influenced the inhibition of leakage and the reduction in carotenoid oxidation as a result of lignification. The impregnations' lack of a significant effect on carotenoid content in the Komaro cultivar may additionally be connected to this tissue's greater susceptibility to de novo synthesis, which is the tissue's response to stress conditions (cutting, impregnation). The possibility of the de novo synthesis of carotenoids in carrot tissue under the influence of abiotic factors that cause physiological stress was also indicated by [PERSON] et al. [45] and [PERSON] et al. [46]. They suggest that the mechanism of de novo synthesis of carotenoids may be based on the expression of gene enzymes involved in the metabolic pathway of these compounds in plants [47]. [PERSON] et al. [46] reported that the increase in the amount of phytoene desaturase transcripts was correlated with carotenoid accumulation. They point to free radicals arising from oxidative stress in the tissue as trigger factors. Figure 6: Color change (**a**) and whiteness index (**b**) for raw and processed samples. Mean \(\pm\) standard deviation. The different letters above the bars indicate a significant difference at \(p<0.05\) for the ANOVA and Tukey post hoc test mean comparisons. The phenolic compound contents in the roots of the tested carrot cultivars before the vacuum impregnation process were 226 mg/100 g DM (Baltimore F1) and 106 mg/100 g DM (Komarno) (Table 4). The application of the vacuum impregnation process and the related changes to the carrots' tissue resulted in a statistically significant increase in the total content of phenolic compounds in both tested cultivars. For the Baltimore F1 cultivar, the content increase averaged about 33% for both 5 and 30 kPa vacuum pressures. In the case of the Komarno, the increase in total phenolic content was 4-fold and 2.5-fold for vacuum pressures of 5 kPa and 30 kPa, respectively (Table 4). The synthesis of phenolic compounds in carrots can be related to the physiological stress to which the tissue is exposed during pre-treatment and cutting, as well as during the vacuum impregnation process itself. In the case of carrots, the physiological response to different postharvest abiotic stresses has been characterized by many authors [48; 49; 50]. The dominant phenolic compounds in the tested carrot cultivars were hydroxycinnamic acids, mainly chlorogenic and ferulic acids and their derivatives. For the Baltimore F1 cultivar, the increase in the total phenolic content was mainly associated with a significant increase in chlorogenic acid for both applied pressure levels, isocumarin at a vacuum pressure of 5 kPa, and ferulic acid at a pressure of 30 kPa.