## 4 Discussion
The reason for the differences in antioxidant activity could be the fact that solvents of different effectiveness were used for extraction [56]. Differences in the ability to scavenge free radicals by currant fruits and their products could result from the presence of additional ingredients in the products. These ingredients could have been characterized by a lower content or lack of antioxidants. which is why the antioxidant activity of the product was lower [47]. The data reported in the literature on the ability to scavenge free radicals determined by the ABTS\({}^{\bullet}\) method are significantly lower than the results of this work. [PERSON] et al. [57] analysed black and red currants. For black fruit they obtained a value of 13.15 umol Trolox/g FM and for those of red colour 44.67 umol Trolox/g FM. [PERSON] et al. [58] for black currant fruits indicated a higher value than the previous author. They reported that the antioxidant activity determined by the ABTS\({}^{\bullet\bullet}\) method was 56.88 umol Trolox/g FM. [PERSON] [56] investigated the antioxidant activity of currant tinctures. The result obtained was lower than the value determined for fruit, amounting to 11.52 umol Trolox/mL. The results presented by other authors regarding the antioxidant property determined in currant extracts using the DPPH\({}^{\bullet\bullet}\) method are much lower than the values given in this work. [PERSON] et al. [57], [PERSON] et al. [15] and [PERSON] et al. [59] determined the ability to scavenge free radicals in black currant extracts. The values they received varied from our results. [PERSON] et al. [15] gave a value of--29.59 umol Trolox/g FM. [PERSON] et al. [57]--109.89 umol Trolox/g FM and [PERSON] et al. [59]--200.3 umol Trolox/g FM. These authors also studied this parameter for red currant. [PERSON] et al. [15] obtained the result--21.9 umol Trolox/g FM, [PERSON] et al. [59]-71.3 umol Trolox/g FM, [PERSON] et al. [59]-71.4 umol Trolox/g FM, [PERSON] et al. [59]-71.5 umol Trolox/g FM, [PERSON] et al. [59]-71.  
et al. [57]--13.73 umol Trolox/g FM. Based on literature review the antioxidant activity of currant products are lower than antioxidant activity of fruits. [PERSON] [56] investigated the antioxidant activity in black currant tincture. It contained 5.0 umol Trolox/mL. [PERSON] et al. [60] showed that the antioxidant activity of black currant and grape juice was 7.9 umol Trolox/mL. Different results for juice were also given by [PERSON] et al. [48]. They showed that in unpasteurized juice the antioxidant capacity was 19.84 and pasteurized 18.47 umol Trolox/mL. [PERSON] et al. [55] reported that in black currant nectar the antioxidant content was at the level of 9 umol Trolox/ml. [PERSON] et al. [48] indicated that the antioxidant activity in apple-currant mousse was 74 umol Trolox/g DM. Own research shows that the antioxidant activity of black currant extracts determined by the FRAP method was in the range 4921-13,485 Trolox/g DM. The literature presents varied values for antioxidant activity determined by the FRAP method. [PERSON] et al. [15] and [PERSON] [61] determined the antioxidant activity for black currant (in fresh material) in value 48.63 umol Trolox/g FM and 107.8 umol Trolox/g FM respectively. [PERSON] et al. [15] also examined the antioxidant activity of red currant and obtained the result--33.8 umol Trolox/g FM. [PERSON] [56] determined the ability to scavenge free radicals for black currant tincture. It was 10.5 umol Trolox/ml. [PERSON] et al. [47] analysed the antioxidant activity of low-sugar and high-sugar black currant jam. It was 20 umol Trolox/ml and 19 umol Trolox/ml, respectively. Based on our results on antioxidant activity and concentration of selected polyphenic compounds in currant fruits, it can be suggested that catechins, sinapinic acid, rathin and hesperidin are the major compounds that influenced the antioxidant activity. However, further studies are needed.