## 3 Results
### Modifications in the Structural and Thermal Properties of Flour Segments Due to PEF Treatment
#### 3.2.5 Thermal Properties
With PEF treatment of oat flour at 52-216 kJ/kg and 4.3-4.5 kV/cm, there was an observed notable increase in onset (54.22-54.64 \({}^{\circ}\)C) and peak temperatures (58.78-59.03 \({}^{\circ}\)C) for the SS1 flour segment (\(\mathrm{T_{o}}^{1}\), \(\mathrm{T_{p}}^{1}\) of 4-A and 4-B, Table 4). Moreover, further increase in the specific energy input applied (421-438 kJ/kg) demonstrated a shift to higher overall transition temperature range of 56.10-74.40 \({}^{\circ}\)C for SS1 (\(\mathrm{T_{o}}^{1}\), \(\mathrm{T_{p}}^{1}\), \(\mathrm{T_{c}}^{1}\) of 2-C and 4-C, Table 4). SS2 sample properties were also found to be affected by the intensity of PEF treatment applied on oat flour. More specifically, higher onset (55.01 vs. 51.82 \({}^{\circ}\)C) and peak temperatures (59.47 vs. 57.05 \({}^{\circ}\)C) were exhibited by SS2 from PEF-treated oat flour at 4.5 kV/cm, 52 kJ/kg compared to Control (refer to \(\mathrm{T_{o}}^{1}\), \(\mathrm{T_{p}}^{1}\), 4-A for Table 4). Similar observation on higher onset temperature (54.68 vs. 51.82 \({}^{\circ}\)C) was also manifested by SS2 from PEF-treated oat flour at 4.3 kV/cm, 216 kJ/kg compared to Control (refer to \(\mathrm{T_{o}}^{1}\) for 4-B, Table 4). Contrary to what was observed in SS1 and SS2 samples, SS3 collected from PEF-treated oat flour at 2.2 kV/cm, 53-218 kJ/kg did not manifest significant changes in its transition temperatures compared to Control (\(\mathrm{T_{o}}^{1}\), \(\mathrm{T_{p}}^{1}\), \(\mathrm{T_{c}}^{1}\), \(\mathrm{\Delta H^{1}}\) of Control, 2-A and 2-B, Table 4). However, PEF treatment of oat flour at higher field strength (4.2-4.5 kV/cm, 4-A, 4-B, 4-C) and specific energy input (421-438 kJ/kg, 2-C and 4-C) led to increased transition temperatures of its SS3 segment, compared to Control (Table 4). * Gelatinisation enthalpy  
SS1 collected from PEF-treated oat flour at specific energy input of 421-438 kJ/kg demonstrated lower gelatinisation enthalpy than the Control (\(\mathrm{\Delta H^{1}}\) of Control, 2-C and 4-C, Table 4). A 91% decrease in the gelatinisation enthalpy was exhibited by SS1 from 2-C and 4-C in comparison to Control. It was also evident that with increased electric field strength (2.1 vs. 4.2 kV/cm) application, at the same level of specific energy input applied, (421-438 kJ/kg) a more drastic change in the gelatinisation enthalpy was noted. With respect to the Control, a 54% and 91% reduction was recorded for SS1 obtained from PEF-treated oat flour at 2.1 kV/cm and 4.2 kV/cm, respectively (\(\mathrm{\Delta H^{1}}\) of 2-C and 4-C, Table 4). On the other hand, it is interesting to note that oat flour PEF treatment at a lower specific energy input levels of 52-218 kJ/kg produced SS1 samples with higher gelatinisation enthalpy compared to Control (refer to \(\mathrm{\Delta H^{1}}\) for 2-B, 4-A, 4-B, Table 4). A 14-18% increase in the recorded gelatinisation enthalpy was observed for SS1 from PEF-treated oat flour at 52-218 kJ/kg. SS2 from PEF-treated oat flour at 2.1-2.2 kV/cm, 53-421 kJ/kg (2-A, 2-B, and 2-C) did not display significant changes in its gelatinisation enthalpy compared to Control (\(\mathrm{\Delta H^{1}}\), Table 4). However, oat flour PEF treatment at 4.3 kV/cm, 216 kJ/kg produced an SS2 sample with substantially higher gelatinisation enthalpy than Control (8.05 vs. 6.66 J/g) (\(\mathrm{\Delta H^{1}}\) of 4-B, Table 4). On the contrary, oat flour PEF treatment at 4.2 kV/cm, 438 kJ/kg produced an SS2 sample with a significantly lower gelatinisation enthalpy than Control (5.13 vs. 6.66 J/g, \(\mathrm{\Delta H^{1}}\) of 4-C, Table 4). SS3 from Control and PEF-treated oat flour did not show significant difference in gelatinisation enthalpy except for SS3 from PEF-treated oat flour at 4.5 kV/cm, 52 kJ/kg (\(\mathrm{\Delta H^{1}}\) of 4-A, Table 4). A 9% increase in the required energy needed to melt starch crystallites was exhibited by SS3 from 4-A compared to Control.