## 3 Results and Discussion
### Color  
Leaf appearance is depicted in Figure 1, and L* (brightness), a* (red-green), and b* (blue-yellow) values are listed in Figure 3. Green fading was observed in all S upon  
Figure 2: TPC, DPPH, and H-ORAC values of parts of _Ocinum basilicum_ cv. ‘Genovese’. TPC: Total polyphenol content, DPPH value: DPPH radical scavenging activity value, H-ORAC value: Hydrophilic oxygen radical absorbance capacity value. The values are expressed as the standard reagents equivalent per dry weight. The results were obtained using Tukey’s test for multiple comparisons. Different letters indicate significant differences at \(p\) < 0.05. Data are expressed as mean \(\pm\) SE (n = 6). comparing the images of NS and S for the steam heat treatment (Figure 1B). S10 showed a significantly faded green color compared with NS, S1, S2, S3, and S5 (Figure 1B). The effect of S treatment on the color was greatest for a* values (red-green), which were significantly higher for S compared with NS, indicating a more faded green color than the latter (Figure 3B). The S treatment was used for maintaining the green color by inactivating chlorophyll-degrade enzyme. However, the results of this experiment showed that the a* values were higher in S than in NS, whereas the green color was not retained by the S treatment. Images of leaves also showed fading of the green color in S compared with that in NS (Figure 1B), which is thought to be due to the heat-induced degradation of chlorophyll to pheophytin. Chlorophyll degradation is affected by acids, temperature, enzymes, and light. Previous studies have shown that longer heating time causes more browning of green leaves [16], and the conversion of chlorophyll to pheophytin is more likely to occur under acidic conditions [23]. Phenolic acids, such as rosmarinic, chicoric, and caffe acids, have been found in Genova [24; 25]. SEM images indicated that S destroyed the leaf tissue structure compared with NS (Figure 1B). Therefore, it was inferred that the S treatment destroyed the leaf tissue structure and degraded chlorophyll into pheophytin under the influence of acidic substances, such as phenolic acids, resulting in the fading of the green color of the leaves. Figure 3: Effects of different treatment conditions on the color of _Octimum basililicum_ cv. ‘Genovese’ tea. (**A,a**) L* values, (**B,b**) a* values, and (**C,c**) b* values. FD: Freeze-drying (\(-\)56 \({}^{\circ}\)C, 48 h), NS: Non-Steaming, S1: Steaming for 1 min, S2: Steaming for 2 min, S3: Steaming for 3 min, S5: Steaming for 5 min, S10: Steaming for 10 min, SD: Shade-drying (25 \({}^{\circ}\)C, 7 days), MD 40 \({}^{\circ}\)C: Machine-drying at 40 \({}^{\circ}\)C, MD 50 \({}^{\circ}\)C: Machine-drying at 50 \({}^{\circ}\)C, MD 60 \({}^{\circ}\)C: Machine-drying at 60 \({}^{\circ}\)C, MD 70 \({}^{\circ}\)C: Machine-drying at 70 \({}^{\circ}\)C, MD 80 \({}^{\circ}\)C: Machine-drying at 80 \({}^{\circ}\)C, MD 90 \({}^{\circ}\)C: Machine-drying at 90 \({}^{\circ}\)C, and MD 100 \({}^{\circ}\)C: Machine-drying at 100 \({}^{\circ}\)C. All results were obtained by [PERSON]’s test for multiple comparisons. Different letters indicate significant differences at \(p<0.05\). Data are expressed as mean \(\pm\) SE (n = 6). We also compared the efficiency of FD and SD, which are frequently used during the drying process. MD was examined at 40, 50, 60, 70, 80, 90, and 100 \({}^{\circ}\)C. FD is considered the best method for maintaining quality, whereas SD is the most economical and commonly used drying method, even though it is weather-dependent [26]. FD retained the maximum green color, followed by MD 40 \({}^{\circ}\)C, whereas SD resulted in a faded green color (Figure 1C). This color retention effect was highest at 40 \({}^{\circ}\)C among the MDs, with significant green fading at \(>\) 50 \({}^{\circ}\)C. Significant differences in L*, a*, and b* values were observed during MD at 40 \({}^{\circ}\)C versus \(>\) 50 \({}^{\circ}\)C (Figure 3).