# Scented Tartary Buckwheat Tea: Aroma Components and Antioxidant Activity
## 2 Results and Discussion
### Identification of the Aroma Compounds in Tartary Buckwheat Tea (TBT)
TBJ had more species but a lower relative content of aroma components. Moreover, the relative content of esters in TBH was the highest (34.35%), accounting for 41.29% of the total. The relative contents of the alkene in TBC and TBR were the highest at 68.29% and 40.26%, respectively, accounting for 70.86% and 40.85% of all components. However, the proportion of olefins and alkanes in TBJ were essentially equal at 32.78% and 34.87%, respectively, which was more than 67.65% of all components. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**No.**} & \multirow{2}{*}{**Compounds**} & \multicolumn{4}{c}{**Relative Contents/\%**} \\ \cline{3-6}  & & **TBH** & **TBC** & **TBR** & **TBJ** \\ \hline
94 & 1-Cyclopropylethanone & - & 0.07 & - & - \\
95 & 2-Butylfuran & 0.30 & - & - & - \\
96 & Butanoic anhydride & 0.71 & 0.13 & 0.06 & - \\
97 & Isovaleric anhydride & - & 0.16 & 0.14 & - \\
98 & Eicosapentaenoic & - & 2.01 & - & - \\
99 & 1-octoxyoctane & - & 0.43 & - & 0.74 \\
100 & 2-(7-Heptadecynyoxy) tetrahydro-2\(H\)-pyran & - & - & 2.05 & - \\
101 & 2,5-Dimethyl pyrazine & 0.93 & - & - & - \\
102 & Isobutyrophenone & 0.51 & - & - & - \\
103 & 2,4’-Bistetrahydrofuran & - & - & - & 0.56 \\ \hline \hline \end{tabular} - means not detected. (Abbreviations: TBH—Huantai tartary buckwheat tea, TBC—tartary buckwheat chrysanthhem tea, TBR—tartary buckwheat rose tea, TBJ—tartary buckwheat jasimine tea)  
\end{table} 
Table 1: _Cont._  
Figure 4: Comparison of volatile components content in tartary buckwheat tea (TBT) (**a**); Varieties of volatile components in TBT (**b**); Analysis of volatile components common to TBT (**c**). (Abbreviations: TBH—Huantai tartary buckwheat tea, TBC—tartary buckwheat chrysanthhem tea, TBR—tartary buckwheat rose tea, TBJ—tartary buckwheat jasimine tea)  
The results derived from the statistical analysis of the common volatile compounds in all samples are shown in Figure 4c. TBH and TBR shared 17 common components, as did TBH and TBJ. Furthermore, 21 shared substances were found in TBC and TBJ, while TBR and TBJ contained 28, showing a high similarity in volatile components. These results were consistent with those obtained from the PCA analysis of the E-nose. Therefore, it is evident that combining the E-nose with PCA and LDA analysis, as well as GC-MS, could successfully distinguish between different types of TBT. Besides their exceptional nutritional value, buckwheat products possess a distinct aroma. The aroma is highly valued by consumers and represents the most significant feature denoting the quality of TBT and can be attributed partly to the basic materials used and partly to the production process. Therefore, consumers prefer TBT due to its unique flavor and beneficial health effects. After performing three different separation techniques, [PERSON] et al. (2019) analyzed the aroma compounds of TBT using GC-MS, identifying 77 compounds of which 35 were quantified according to the available standards. The compounds that contributed significantly to the aroma of TBT included 2,5-dimethyl-4-hydroxy-3(2_H_)-furanone, nonanal, 2,3-diethyl-5-methylpyrazine, benzeneacetaldehyde, maltol, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine, and trimethylpyrazine. Moreover, several nutritional and bioactive compounds, such as linoleic acid, niacin, vanillin acid, 7-hydroxycoumarin, and butylated hydroxytoluene, were determined in this study. In addition, further research determined the volatile components of two kinds of TBT, whole grain tea and whole plant tea ([PERSON], 2017). GC-MS analysis identified 14 aroma components in whole grain tea and whole plant tea, with 3-ethyl 2,5-dimethylpyrazine as the main component. However, some differences were evident in the aroma composition profile. Nevertheless, the relative content of these compounds varied among the different types of TBT, indicating that the raw materials affected the content of aroma compounds significantly, resulting in odor differences in the tea ([PERSON] and [PERSON], 2018).