## 2 Results and Discussion
### Odorants Quantitation
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & & \multicolumn{2}{c}{**TNS**} & \multicolumn{2}{c}{**TNSM**} & \multicolumn{2}{c}{**TNY**} & \multicolumn{2}{c}{**TBY**} \\ \cline{3-10}
**Odorant** & \begin{tabular}{c} **OTC 1** \\ **(mg/L)** \\ \end{tabular} & \begin{tabular}{c} **Concentration 2** \\ **(mg/L)** \\ \end{tabular} & \begin{tabular}{c} **OAV 3** \\ **(mg/L)** \\ \end{tabular} & \begin{tabular}{c} **Concentration** \\ **(mg/L)** \\ \end{tabular} & \begin{tabular}{c} **OAV** \\ **(mg/L)** \\ \end{tabular} & \begin{tabular}{c} **Concentration** \\ **(mg/L)** \\ \end{tabular} & \begin{tabular}{c} **OAV** \\ **(mg/L)** \\ \end{tabular} & \
\begin{tabular}{c} **Concentration** \\ **(mg/L)** \\ \end{tabular} &
\begin{tabular}{c} **OAV** \\ **(mg/L)** \\ \end{tabular} \\ \hline
**1** & 0.0005 & 0.0218  & 44 & 0.00188  & 4 & 0.0298  & 60 & 0.000748  & 1 \\
**3** & 0.015 & nd & - & nd & - & nd & - & nd & - \\
**5** & 0.0012 & nd & - & nd & - & nd & - & nd & - \\
**7** & 0.0087 & 0.0138  & 2 & 0.00326  & \textless{1} & 0.00445  & \textless{1} & 0.00521  & \textless{1} \\
**10** & 3 & 0.617  & \textless{1} & nd & - & 0.568  & \textless{1} & 3.03  & \textless{1} & 3.03  & \textless{1} \\
**12** & 2.4 & 0.00251  & \textless{1} & 0.236  & \textless{1} & 0.350  & \textless{1} & 0.274  & \textless{1} \\
**13** & 0.0052 & 0.0560  & 11 & 0.0835  & 16 & 0.0514  & 10 & 0.101  & 20 \\
**14** & 0.49 & 0.129  & \textless{1} & 0.0760  & \textless{1} & 0.265  & \textless{1} & 0.251  & \textless{1} \\
**17** & 0.14 & 2.99  & 21 & 2.70  & 19 & 4.29  & 31 & 2.30  & 16 \\
**18** & 0.025 & 0.334  & 13 & nd & - & 0.390  & 16 & 0.407  & 16 \\
**22** & 0.068 & 1.22  & 18 & 0.857  & 13 & nd & - & 0.961  & 14 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Concentration, OTC, and OAV for odorants in tilia-based meads. quantitated aldehydes was furan-2-carbaldehyde, which was detected in one buckwheat-based mead (BNS) and three tiling-based meads (TNS, TNY, and TBY). Its concentration did not exceed its odor threshold in almost all cases (except the TBY sample, in which its OAV was equal to 1), which suggests that this compound did not have a meaningful influence on the final aroma of tested meads. Acids represented by sweaty butanoic acid, malty and sweaty 2- and 3-methylbutanoic acid, and honey- and bees wax-like phenylacetic acid were determined in almost all tested samples (the only exception was phenylacetic acid in the TNY sample). Concentrations of butanoic acid in all tested samples were below its odor threshold concentration, but 2- and 3-methylbutanoic acid scored concentrations above its odor threshold in all buckwheat-based meads and in the ABY sample, with the highest value of 2.62 mg/L for the BNY sample. Those results are in agreement with sensory evaluation data, as all buckwheat-based meads had relatively high malty scores. Concentrations of 2- and 3-methylbutanoic acid for buckwheat-based meads are relatively higher than those obtained in our previous research for mead made from multi-floral honey (0.868 mg/L) [13]. The last of the quantified acids with a pleasant, bees wax-like odor was an important odorant in almost all tested samples (except TNY). The concentration of this compound was visibly higher for buckwheat-based meads when compared to acacia- and tilia-based meads. Higher concentrations resulted in high OAVs, making it the second most important odor-active compound in buckwheat-based meads. Those concentrations (ranging from 4.05 mg/L for the BNSM sample to 3.32 mg/L for the BBY sample) are visibly higher than those observed by [PERSON] and [PERSON] for meads prepared from heated and unheated wort (0.748 mg/L and 0.77 mg/L, respectively). Meads prepared from acacia and tilia honey scored concentrations of phenylacetic acid similar to or slightly higher than those observed by [PERSON] and [PERSON] [11]. Caramel-like 2,5-dimethyl-3(2\(H\))furanone was detected in almost all tested meads, except BNY and TNSM samples.