## 3 Results and Discussion
), which was probably due to the pasteurization (70 \({}^{\circ}\)C) used during its production and high macerate moisture (54.60 \(\pm\) 0.99%), creating conditions for the further course of the garlic aging process. Apart from changes in the content of polyphenolic compounds, their profile also changes during the production of black garlic. According to the literature, the content of phenolic acids may increase even eight-fold, among which derivatives of hydroxycinamic acid dominate [31; 32; 51], which is attributed to the high stability of these compounds compared to other phenolic structures [51; 55; 56; 57]. The profile of flavonoid compounds is also changing, the amount of which may increase by about four [51] or five times [52]; however, due to the very large variety of their chemical structure and thermal stability [57], the share of individual flavonoids varies widely at different stages of the garlic aging process, depending on the thermal conditions and the production time of black garlic [51; 52; 57]. Black garlic is known primarily for its antioxidant properties, which are determined by the increasing content of phenolic components during the aging process, as well as changes in the content and profile of sulfur-organic compounds [13; 20; 41; 52]. Therefore, the study investigated the antioxidant activity of fresh, unprecedented garlic (WG), black garlic (BG-C) obtained after 45 days of heat treatment at 70 \({}^{\circ}\)C and 80% relative humidity and the products of its processing--i.e., powder (BG-P) and spreading paste (BG-S), (Figure 3b). All garlic samples were characterized by a high ability to deactivate synthetic cation radicals ABTS\({}^{\star\star}\) (on average 500.50 \(\pm\) 165.28 uM TEAC/1 g d.m. ), and there were statistically significant (\(p\) < 0.05) differences in this parameter between the tested samples. White, unprocessed garlic (WG) was characterized by over two times lower antioxidant potential (232.95 \(\pm\) 4.06 uM TEAC/1 g d.m.) than black garlic (on average, all black garlic products showed activity at the level of approximately 589.68 \(\pm\) 42.05 uM TEAC/1 g d.m.). The results are similar to these obtained by other authors [18; 31; 32; 41], which show a several-fold (2-9) increase in the antioxidant capacity of garlic during long-term heat treatment, leading to the production of black garlic, depending on the time and thermal conditions of the aging process [16; 17; 19; 30; 41; 42] or the type of aged garlic (heads/cloves) [41; 42]. Some authors show even several dozen times higher antioxidant activity of black garlic compared to white garlic [13; 48]. However, the literature lacks comparative data for various black garlic processing products. According to our research, among the analyzed black garlic products, the highest antioxidant activity (similarly to the total content of polyphenols) was found in black garlic spreading paste (BG-S), where the value of this parameter reached an average of 638.46 \(\pm\) 3.37 uM TEAC/1 g d.m. (Figure 3b). According to the literature, the key compounds shaping the high antioxidant potential of black garlic include, among others, various polyphenolic or organosulfur compounds, both those that are present in fresh, unprocessed garlic and those that arise during its processing [13; 41]. Already during the pre-treatment of garlic and during its grinding, biting the clove), odorless sulfur compounds such as allin (S-allyl-L-cysteine sulfoxide, SAC) and \(\gamma\)-glutamyl-S-allyl-cysteine (GSAC), are metabolized under the influence of the enzyme released then--allinase--to strongly aromatic, irritating substances that determine the specific sharp taste of garlic, such as allicin (diallyl thiosulfonate) and its diallyl sulfide derivatives, such as DAS (diallyl sulfides), DADS (diallyl disulfides), DTS (diallyl trisulfides) and others [12, 58].