## 2 Results and Discussion
### The Profile of Volatiles Compounds in Bee Products
\begin{table}
\begin{tabular}{l l l l l l l l l l} \hline \hline \multicolumn{1}{c}{**No**} & \multicolumn{1}{c}{**Compound**} & \multicolumn{1}{c}{**Aroma Description**} & \multicolumn{1}{c}{**LRI**} & \multicolumn{1}{c}{**LRI**} & \multicolumn{1}{c}{**LRI**} & \multicolumn{1}{c}{**Resurance**} & \multicolumn{1}{c}{**Ree Products**} & \multicolumn{1}{c}{**Resurance**} & \multicolumn{1}{c}{**Ree Polline**} & \multicolumn{1}{c}{**Honey**} \\ \hline X38 & 1-round & wavy & 1561 & 1561 & 1.35 \(\pm\)0.041\({}^{\rm o}\) & - & - & - &  
The next bee product with the high number of volatile compounds (32) was beebread. It contained 15 alkanes (X1, X2, X3, X4, X5, X6, X7, X8, X9, X11, X16, X17, X18, X25, and X27), four aldehydes (X13, X21, X28, and X37), five acids (X31, X45, X46, X49, and X55), two benzenes (X15 and X19), two ketones (X15 and X19), and others (disulfides, furans, pyrroles, and lactones). The results indicated a high contribution of alkanes in beebread, representing 47% of all identified compounds, and their 57.7% contribution to the aroma profile (Figure 1). Volatiles detected in the beebread belonged to nine out of the 13 chemical groups classified in the bee products. Moreover, it was the only sample from the tested bee products whose volatile profile was common with the profiles of the other samples, probably since it is a combination of honey and pollen [3; 29]. Furthermore, our study showed that the volatiles present in bee pollen played a more important role in creating the profile of volatile compounds of beebread than these of honey. To the best of our knowledge, there is paucity of data on the profile of volatile compounds in beebread. Results of a study by [PERSON] et al. [30] also showed 32 volatiles in beebread from Lithuania. Comparing the beebread from Poland and Lithuania, the same 11 volatiles (2,4-dimethyl-heptane, nonane, decane, dimethyl disulfide, dodecane, octanal, nonanal, acetic acid, furfural, benzaldehyde, and hexanoic acid) were present in both samples. As mentioned above, the main compounds in beebread in our research were decane (X6), furfural (X32), 2,6,11-trimethyl-dodecane (X9), and 1-tridecene (X25), each contributing approximately 9% to the total volatiles (Table 1). However, the beebread from Lithuania had high contents of dimethyl sulphide, 1-heptadecene, acetic acid, nonane, and furfural, accounting for 20.0%, 13.9%, 13.4%, and 9.8% of the total volatiles, respectively [30]. Furfural was detected in the samples from Lithuania and Poland. Moreover, its content in both beebreads was the same (9.8% of the aroma profile). It is common knowledge that the furfural concentration is associated with the heat treatment [31], therefore, the high contribution of this compound may depend on the extraction method (SPME). The next compound with a high contribution in the beebread from Lithuania was acetic acid. However, its content in the sample from Poland was lower by 6.3%. The source of acetic acid in beebread is unknown, but there are two possibilities. As mentioned above, the beebread is a mixture of honey and bee pollen, which undergoes fermentation by enzymes of the bee's saliva and Lactobacillus [32], resulting in the formation of acetic acid. On the  
Figure 1: Chemical classes contribution of volatile compounds detected in bee products. other hand, acetic acid--as a biological metabolic intermediate--occurs naturally in plant juices [33], which may also be collected by bees. In honey, we identified 20 compounds in total, including: six acids (X31, X45, X48, X49, X53, and X55), six monoterpens (X20, X22, X30, X39, X41, and X50), three volatiles from the group of alcohols (X33, X51, and X52), two aldehydes (X28 and X37), and one compound from each of the following groups: Disulfides (X12), furrans (X32), and lactones (dihydro-4-methyl-2(3\(H\))-furanone). These results concerning the detected chemical families are consistent with findings reported by other authors [20].