## 3 Results and Discussion
### Effect of HPP on RS Content
#### 3.2.1 Effect of Pressurization Time and Pressure Value on RS Concentration
Changes in the structure of starch in our study are shown, for example, on the sample of chickpeas treated with 600 MPa pressure for 3, 6, and 9 min (Figure 6). We can see the change in the structure of the starch granules at successive 3, 6, and 9 min (Figure 6b-d) of 600 MPa pressure compared with the unpressurized sample (Figure 6a). The granules of untreated chickpea starch have a spherical morphology, and as the pressurization process is extended, the granules are distorted. Microscopic images showed the enlargement and swelling of HPP-treated starch granules, and we can also see the initial aggregation, which may explain the formation of gel-like granules during the HPP-induced gelatinization process. The results of RS content in the 600 MPa pressure-treated chickpea samples at 3, 6, and 9 min shown in Figure 4a show a gradual decrease in RS content with increasing pressure time, which is probably related to the HPP-induced starch gelatinization process, as can be seen in the microscopic images (Figure 6). One of the earliest studies investigating the effect of HPP on starch properties dates back to 1981 and focused on the gelatinization of potato starch under the influence of HPP [55]. Since then, more studies have delved into this issue, but the majority have explored \"typical\" starchy products like cereals and tubers, with limited reports on the effects of HPP on legume seeds as a source of starch [56; 57; 58; 59; 60]. In the current study, the RS content changed significantly under the influence of time from both cooled and uncooled chickpeas (Figure 4a,c), beans (Figure 3a,c), and lentil samples (Figure 5a,c). Further, under the influence of pressure, significant changes were observed in both cooled and uncooled beans (Figure 3b,d) and chickpeas samples (Figure 4b,d), as well as in lentil samples (Figure 5b,d). [PERSON] et al. (2017) demonstrated no significant differences in the RS content of chestnut flour treated with HPP (0.1, 400, 500, and 600 MPa for 10 min). They indicated that HPP did not cause a change in RS content [61], but in our study, the RS content changed significantly under pressure in the case of all tested plants. In another study by [PERSON] et al. (2016), the effect of HPP on the properties of lentil starch under different pressures was studied, and the results showed that a decrease was noted in RS content after applying pressures of 400 MPa [62], which was also confirmed by our study (Figure 5b). However, the authors observed a significant increase in the RS content of lentil starch at a pressure of 600 MPa, which was explained by the rise in temperature during the process due to the adiabatic effect when higher pressure was applied [62]. In our study, the temperature during pressurization did not change, which may be related to opposite observations (Figure 5b). On the other hand, in a study reported by [PERSON] et al. (2014) [63], the effect of HPP on rice starch was investigated. It was shown that higher pressure (600 MPa) resulted in lower RS content to lower pressure (200 MPa), which was also confirmed in our studies, especially with pressure 600 MPa, as depicted in Figures 3b, 4b and 5b.