## 3 Results
### Effect of HPP on the Nutrient Composition of Cauliflower  
Only the HPP cauliflower treated at 600 MPa for 2 min was chosen to be further analyzed chemically (until day 28). The choice of 600 MPa and 2 min was selected due to lower bacterial counts (compared to the other HPP parameters), and because 5 min did not differ significantly from 2 min in the abovementioned quality parameters (Table 5).  
Figure 1: Visual comparison of selected pieces of cauliflower after HPP treatment of 400 MPa/2 min until day 42.  
No studies on the effects of HPP on antioxidant activity (AOC) in cauliflower were found. For other vegetables, the effects of HPP on AOC have been shown to vary. [PERSON] et al. subjected white cabbage to HPP (200/400/600 MPa, 20/40 \({}^{\circ}\)C), and found that 600 MPa gave significantly higher retention of AOC with almost four times higher activity compared to 200 and 400 MPa [45]. [PERSON] et al. (2011) also found the same trend, where swedes pressurized at 600 MPa were insignificantly higher than the control and had 2.6 times higher AOC than at 400 MPa. This could indicate that lower pressure levels would not be as beneficial for cauliflower, although this would have to be tested first [42].  
Other studies on HPP's effects on TPC in vegetables show that in most cases, pressure increases the concentration of phenolic compounds. For instance, [PERSON] et al. (2014) found that among HPP treatments for white cabbage, 600 MPa yielded the highest retention of TPC (393 mg GAE/100 g DW) compared to lower pressures. [PERSON] et al. also observed a similar trend in swedes, where 600 MPa gave the highest retention of TPC (399 mg GAE/100 g DW) compared to lower pressures [42; 45]. These findings indicate that higher pressures for cauliflower could be beneficial in nutrient retention.  
Ascorbic acid (AA) is regarded as one of the most heat-sensitive vitamins and is therefore used as a key indicator of the effects of processing on vitamins ([PERSON] et al., 2000). The results in Table 5 represent the influence of different processing conditions on the content of AA (mg/100g dry weight (DW)) in pieces of cauliflower. The results reveal that HPP had a negative impact on (\(p<0.05\)) AA content. The treated samples resulted in a 40% reduction in AA compared to the control. HPP is a mild processing condition that does not significantly affect low-molecular-weight molecules, such as AA, because of the low compressibility of covalent bonds [31]. On the other hand, some degradation of AA could result due to remaining active enzymes that were not inactivated by the 600 MPa pressure.  
The effects of HPP on AA in vegetables and fruits were shown to vary. Furthermore, [PERSON] et al. found a significant reduction in AA in white cabbage after HPP (600/400 MPa, 20 \({}^{\circ}\)C, 5 min) compared to a non-treated control. Their control had approximately 840 mg AA/100 g DW, while 400 MPa yielded under 100 mg/100 g DW, and 600 MPa yielded approximately 620 mg/100 g DW [45]. A similar trend was also observed in [PERSON] et al., who subjected swede to the same HPP conditions as the mentioned study above, with 81% retention of AA at 600 MPa (664 mg/100 g DW), while 400 MPa gave the lowest retention of AA (257 mg/100 g DW) [42]. They hypothesized that the high retention at 600 MPa could be a result of higher inactivation of the POD enzyme.