## 3 Results and Discussion
### Characteristics of Extruded Corn Snacks
#### 3.2.1 Chemical Composition and Pro-Health Components in Extruded Corn Snacks with Fruit Pomace
In the context of the health-promoting properties of anthocyanins, namely their anti-mutagenic, anticarcinogenic, and antihypertensive activity, and reduced risk of chronic diseases and neuronal degeneration [50; 51; 52], this seems to be an important achievement of this work. Especially anthocyanins from chokeberries show inhibition of cancer cell proliferation and antimutagenic, hepatotoxicity, antidiabetic, and cardioprotective effects [53], which additionally supports the fact that health-promoting extruded corn snacks supplemented with chokeberry pomace can be produced. Taking into consideration the fact that extrusion could cause a reduction in the polyphenol content in the range of 24% to 46% [17], it should be noted that the additive-enriched corn snacks applied in this work are high in polyphenic compounds, despite the loss of these components resulting from the partial depolymerization, decarboxylation (in the case of phenolic acids), and the polymerization of phenolic compounds and tannins [18] during extrusion. Among all analyzed fruit pomaces, the largest increase in polyphenols, phenolic acids, flavonoids, and anthocyanins in extruded corn snacks guarantees PCHB (Table 4). The results of the AA analysis of the samples determined by the method with a synthetic free radical ABTS are summarized in Table 3. It was found that each of the additives contributed to an increase in this type of activity of the extrudates, on average by 265% for PCHB added, about 108% for PCH, and 180% in the case of PBC (Table 3). AA of the analyzed snacks incorporating fruit pomace was adequate for the content of total polyphenols, as was evidenced by the strong positive correlation between the total phenolic content and ABTS (r\({}^{2}\) = 0.829). Exceptions were observed for ECHB-20 and EPBC20, which have identical AA despite significant differences in the total polyphenol content. Most likely, this must be attributed to the fact that other compounds, not analyzed in this research (such as tannins as well as new compounds formed by extrusion, such as Maillard reaction products or the conversion of less active antioxidants into more active antioxidants [54]), contributed to AA. AA was also calculated as EC\({}_{50}\), i.e., the concentration of antioxidants necessary to neutralize 50% of the ABTS present in the sample; the lower the EC\({}_{50}\) value, the higher the antioxidant activity of the polyphenols in the sample. When AA was calculated as Trolox (TEAC) and EC\({}_{50}\), an inverse relationship was clear. Among the analyzed samples, snacks with a 20% share of PCHB had the highest AA because their EC50 was the lowest. In studies conducted by [PERSON] et al. [55], the brewer's spent grain was applied, but with no effect on the content of polyphenols or the antioxidant activity of the investigated samples. Moreover, adding the cauliflower by-product to extrudates did not increase the polyphenol level, but it had a detrimental effect on the antioxidant activity [23]. Similarly, the addition of brewer's spent grain to cereal extrudates resulted in no observed changes in polyphenol levels or antioxidant activity [56]. In [PERSON] et al. 's [22] study on the effect of blueberry, cranberry, concord grape, and raspberry additions on the amount of polyphenols in extrudates, there were no changes in the amount of these compounds, most likely as a result of a too low share--only 1%. However, the addition of red cabbage to cereal snacks resulted in a marked increase in the polyphenol content and antioxidant activity [56]. Other research [57] dealing with cereal snacks supplemented with defatted blackcurrant seed noted a 2- to 10-fold increase in the levels of polyphenols and a 2- to 11-fold increase in antioxidative activity as compared to the control. [PERSON] et al. 's [58] investigation on the enrichment of cereal-based extrudates with cactus fruits led to an increase in the antioxidative activity of the final product, adequate to the amount of the applied supplement. Similarly, [PERSON] et al.