## 3 Results
### Impact of the Selected Processing Conditions on the Characteristics of AP
#### 3.2.2 Antioxidant Activity  
The AP's antioxidant activity was assessed both before and immediately after the treatments using the DPPH and ABTS assays. The results are presented in Figure 3. Both assays showed comparable inhibitory patterns, as the treated AP samples exhibited a statistically significant increase in inhibition relative to the untreated or blanched AP. The DPPH antioxidant experiment revealed that BL significantly enhanced the antioxidant activity of AP by 33.4%, increasing it from 0.195 \(\pm\) 0.016 mmol TE/100 g to 0.260 \(\pm\) 0.027 mmol TE/100 g, as seen in Figure 3A. In general, all of the processing methods that were examined significantly improved the antioxidant activity. The results showed that CTP, US, and PEF had similar effects with statistical significance (\(p<0.05\)). Significantly, the DPPH scavenging activity of HPP-pasteurized samples increased by 66.7% (\(p<0.05\)) compared to BL samples, making it the highest among the technologies examined in this work. The increase in antioxidant activity resulting from HPP may be attributed to the extraction of antioxidant compounds from the AP plant cells, which were then dissolved in the AP [20]. The increase in PEF-mediated DPPH radical scavenging activity in other technologies may be attributed to the electroporation of plant cells, which leads to the extraction of antioxidants from the vacuoles [21]. On the other hand, in the case of US processing, the increase in scavenging activity may be linked to the cavitation phenomenon, which causes the disruption of plant cells and leakage of cell contents [22]. Figure 2: Instrumental colour parameters of AP before and immediately after treatment at the selected conditions for each technology. (**A**) L* is lightness, (**B**) a* varies from green to red, (**C**) b* varies from blue to yellow, (**D**) total colour difference/variation (\(\Delta\)E*) and (**E**) visual appearance of final product. Different letters above the bars on the same graph represent significant statistical differences (\(p<0.05\)) between treatments. Regarding the ABTS assay, a similar scenario was found to that observed for the DPPH scavenging assay. The BL process per se increased the ABTS scavenging activity by 30.3% compared to the raw AP (Figure 3B). A general increase in the ABTS radical scavenging activity was observed, regardless of the pasteurization methodology, yet with different degrees of magnitude. In fact, the highest increase in antioxidant activity was observed for samples processed by HPP (58.8% compared to BL samples), while a smaller increase was observed for samples processed by CTP, US, and PEF, as seen in Figure 3, with an overall increase of 34.6, 34.2 and 45.3%, respectively, when compared to BL samples. The antioxidant activity of pasteurized foods can indeed be affected by the presence of air in the food product, such as when it is stored in a container with empty space or vacuum sealed. The antioxidant activity of AP was quantified after exposing it to a temperature of 90 \({}^{\circ}\)C for 30 min, with and without the presence of oxygen. Compared to the fresh AP, the samples that were heated in the presence of oxygen exhibited a notable reduction in DPPH scavenging activity, decreasing from 0.71 to 0.68 g/kg TE (fresh weight). Similarly, in the ABTS assay, the activity decreased from 0.27 to 0.26 g/kg TE. Under anaerobic conditions, the outcomes were comparable to those of the recently obtained AP [23]. This outcome is predictable and can be ascribed to the probability of the generation of reactive oxygen species that can oxidize the antioxidants, so limiting their capacity to counteract free radicals. Consequently, the free radicals have the ability to further damage the constituents of food, resulting in a decrease in antioxidant capacity [24].