## 3 Results
### Results of Analytical Methods
#### 3.3.2 Results of Measurement of Antioxidant Capacity  
For the Bonita (white flesh) variety, the antioxidant capacity at the time of sample preparation was nearly equivalent for untreated samples (C), samples treated with apple pomace extract (AP), and samples treated with citric acid (CA) (12.40-17.14 mgAA/100 g) (Figure 5). In comparison, the value of the sample soaked in the extract of chokeberry (CP) was approximately half (6.78 mgAA/100 g), while that of the sample soaked in the ascorbic acid solution (AA) was twice as high (25.75 mgAA/100 g). The treatment had a significant effect (F(4;10) = 384.173; \(p<0.001\)). A study of 11 varieties found that the FRAP value ranged from 2.5 to 7.5 mgAA/100 g [43].  
After storage, samples treated with no treatment (C), the citric acid solution (CA), and plant extracts (AP and CP) had similar values (10.89-15.02 mgAA/100 g). The highest value was obtained for the sample treated with the ascorbic acid solution (AA) (37.64 mgAA/100 g). The storage time had a significant effect (F(1;10) = 43.005; \(p<0.001\)).  
In terms of storage trends, the control (C) and citric acid solution-treated (CA) samples showed a slight decrease (15.3% and 12.4%, respectively). The sample soaked in apple pomace extract (AP) exhibited a slight increase (12.5%), while the ascorbic acid solution-treated sample demonstrated a more significant increase (46%). The most pronounced increase was observed in the sample treated with chokeberry pomace extract, reaching 61%. The interaction of treatment and storage time had a significant effect (F(4;20) = 42.344; \(p<0.001\)).  
For the Covington variety (orange-fleshed), the antioxidant capacity at the time of sample preparation was nearly similar to the untreated (C) and plant extract-treated (AP, CP) samples (19.22-29.50 mgAA/100 g). In comparison, the sample soaked in the ascorbic acid solution (AA) exhibited nearly double the value (38.15 mgAA/100 g), while the sample treated with the citric acid solution (CA) demonstrated approximately three times the value (68.51 mgAA/100 g). The treatment had a significant effect (F(4;10) = 798.087; \(p<0.001\)).  
After a duration of five days, the antioxidant capacity exhibited similar values in the control (C) and plant extract-treated (AP, CP) samples (22.18-27.86 mgAA/100 g),  
Figure 5: Results of antioxidant capacity of treated Covington (dark orange) and Bonita (white) varieties of sweet potatoes after storage. Each value is expressed as the mean \(\pm\) standard deviation. The presence of different letters indicates that the groups in question are significantly different. Higher case letter: comparison of treatment at the fixed storage time. Lower case letter: comparison of storage time at fixed treatments.  
whereas in the samples treated with ascorbic acid (AA) and citric acid (CA), the values were about twice as high (61.19-70.19 mgAA/100 g). The storage time had a significant effect (F(1;10) = 83.571; \(p<0.001\)).  
With regard to storage trends, the sample treated with chokeberry pomace extract (CP) showed a decrease of 25%. In all other cases, an increase was observed, with the smallest change observed in the citric acid solution-treated sample (2.4%), followed by the apple pomace extract-treated sample with a 15% increase. The antioxidant capacity of the control sample exhibited a 45% increase, while the ascorbic acid-treated sample demonstrated a 60% increase. The interaction of treatment and storage time had a significant effect (F(4;20) = 55.940; \(p<0.001\)).