## 2 Results and Discussion
### Analysis of Aroma  
The volatile organic compounds analyzed by SPME-GC-MS are presented in the Supplementary Materials (Table S1), and a chromatogram of each sample is exhibited Figure S2 in the Supplementary Materials. The chemometric analysis, via Principal Component Analysis (PCA), was instrumental in distinguishing the aroma profiles of the microencapsulated jasmine instant tea. The PCA plots provide a visual and quantitative assessment of the distribution and variance of the samples, indicating the relative success of each encapsulating agent in preserving the aromatic integrity of the jasmine instant tea.  
As shown in Figure 4 the PCA (Principal Component Analysis) groups the analyzed samples into different clusters based on their volatile organic compound profiles. The variance explained by the first principal component (PC1) is 59.5%, and by the second principal component (PC2) is 15.1%. Through this analysis, it was found that tea brewed from tea leaves formed a distinct cluster compared to the samples prepared from jasmine instant tea. This clustering highlights the significant difference in the volatile profiles, likely due to the concentration and drying processes involved in the production of instant tea [37]. The high temperatures and vacuum conditions typically used during concentration and spray drying can cause the evaporation or degradation of volatile organic compounds, leading to a reduced aromatic profile in instant tea [38].  
The PCA results also allowed the differentiation of jasmine instant tea samples based on the encapsulating agents used. For instance, samples encapsulated with gelatin showed closer clustering to the fresh tea reference point compared to other encapsulating agents like acacia gum, carboxymethylcellulose (CMC), and maltodextrin. This indicates that gelatin was more effective in preserving volatile organic compounds that contribute to the aroma of the tea. The ability of gelatin to retain these key aromatic compounds could be attributed to its molecular structure, which forms a dense, protective matrix around the volatile organic compounds, limiting their diffusion and evaporation during the spray-drying process [39].  
Furthermore, the encapsulation efficiency of gelatin is likely influenced by the size of the microcapsules, as seen in Supplementary Materials Figures S1 and S3. The larger size of the gelatin-based microcapsules allows for greater encapsulation capacity and slower release rates, resulting in better retention of the volatile organic compounds. This suggests a potential correlation between the microcapsule size, the release dynamics of the aromatic compounds, and the overall sensory quality of the tea.  
Figure 3: Scanning Electron Microscopy (SEM) images of microencapsulations produced with various wall materials. The images show the morphology and surface characteristics of microencapsulations made from gelatin, acacia gum, carboxymethylcellulose (CMC), and maltodextrin. Each image highlights the structural differences and surface textures of the microencapsulations depending on the wall material used.  
Our PCA findings (Figure 4) support the conclusion that different encapsulating agents influence aroma retention in jasmine instant tea to varying degrees. Specifically, the success of gelatin in preserving key volatile organic compounds suggests it may be an optimal choice for encapsulation in instant tea products that prioritize high sensory quality.