## 3 Results
### Trichome Structure  
The number of trichomes on the leaf surface was between 5-7 trichomes/2 mm\({}^{2}\) area of the leaf surface (square area, Figure 7A). Figure 7B-H shows representative micrographs of trichomes on the surface of Thai basil leaf samples at a magnification of 300 times. Fresh samples (Figure 7B) showed a more intact structure than rehydrated samples (Figure 7B-H). PEF-nested samples had less collapsed surface in both convective (Figure 7E) and vacuum drying (Figure 7F) than the rehydrated control and control-rested treated samples (Figure 7G,H). When examined under a magnification of 700 times, intact trichomes can be generally seen as expanded structures sticking out from the surface of the leaves (Figure 8A). Partially collapsed trichomes were also found on the fresh samples (Figure 8B), but in very small numbers (less than 5%). Rehydrated samples showed different kind of trichomes: intact (Figure 8C), partially collapsed (Figure 8D), and collapsed trichomes (Figure 8E). Intact trichomes were seen more in fresh samples than in the rehydrated samples. When the area covered by a trichome was measured (Figure 8F), the area in fresh samples and PEF-nested, convective dried samples were found to be the largest (Table 3). In both convective and vacuum drying, the percentage of collapsed trichomes in PEF-nested samples was significantly lower than in control and control-rested samples (\(p<0.05\)). In these samples, the area of partially collapsed trichomes were between 78-97% of the intact trichomes. Figure 6: Total color change (\(\Lambda\)E) of Thai basil leaf samples subjected to different pretreatments (control, control-rested, and PEF nested) prior drying with convective drying and vacuum drying to the moisture ratio of 0.2, 0.1, and 0.05. Reported are averages and standard deviations of 15 measurements. Different letter superscripts represent statistically significant differences (\(p<0.05\)). Figure 7: Representative micrographs of fresh and rehydrated Thai basil leaf samples subjected to various treatments and examined using a high-resolution optical microscope: micrograph showing the number of trichomes in a 2 mm\({}^{2}\) area (**A**) with a magnification during acquisition of 100\(\times\), fresh (**B**), convective dried control (**C**), vacuum dried control (**D**), convective dried, PEF-rested (**E**), vacuum dried, PEF-rested (**F**), convective dried, control-rested (**G**), vacuum dried, control-rested (**H**). The magnification of the micrographs (**B–H**) during acquisition was 300\(\times\). Figure 8: Representative 3-D surface images of different levels of intact and damaged trichomes found in fresh and rehydrated Thai basil leaves. Fully inflated trichome in fresh samples (**A**), damaged trichome in fresh samples (**B**), inflated trichome found in rehydrated samples (**C**), partially inflated trichome in rehydrated samples (**D**), damaged trichomes in rehydrated samples (**E**). Schematic of trichome area measurement using the built-in software of the microscope; the measurement area has a value of 2046.67 μm2 (**F**). The magnification of the image during acquisition was 700\(\times\).