## 2 Results and Discussion
### Volatile Maillard Reaction Products Formation

Table 2: Volatile compounds identified in control biscuits (CB), rye-buckwheat biscuits (RBB) and in biscuits with increasing ruin addition (RBB-L, RBB-M, RBB-H, respectively). The compounds were identified by comparing its mass spectrum and Rl with data in the literature: tentative identification. Results are expressed as Peak Area \(\times 10^{6}\). \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Compound** & **RI \({}^{\star}\)**\(\,\)**tr** & **RI \({}^{\circ}\)** & **Odor Description** & **CB** & **RBB** & **RBB-L** & **RBB-M** & **RBB-H** \\ \hline _Aldehydes_ & & & & & & & & \\ _Ieacanal_ & 1084 & 1078 & grassy, green & 31,297 \(\pm\) 1228 \({}^{\circ}\) & 27,495 \(\pm\) 644 \({}^{\circ}\) & 15,753 \(\pm\) 695 \({}^{\circ}\) & 15,812 \(\pm\) 917 \({}^{\circ}\) & 11,405 \(\pm\) 133 \({}^{\circ}\) \\ _Pyrazine_ & & & & & & & \\ methylpyrazine & 1253 & 1266 & nutty; cocon & 1002 \(\pm\) 55 \({}^{\circ}\) & 1041 \(\pm\) 11 \({}^{\circ}\) & 692 \(\pm\) 65 \({}^{\circ}\) & 1318 \(\pm\) 9 \({}^{\circ}\) & 1785 \(\pm\) 73 \({}^{\circ}\) \\ 2-6-dimethylpyrazine & 1308 & 1310 & nutty, earthy & nd & nd & 396 \(\pm\) 26 \({}^{\circ}\) & 521 \(\pm\) 30 \({}^{\circ}\) & 633 \(\pm\) 29 \({}^{\circ}\) \\ 2-5-dimethylpyrazine & 1320 & 1329 & nutty, roasty & 518 \(\pm\) 18 \({}^{\circ}\) & 530 \(\pm\) 51 \({}^{\circ}\) & 484 \(\pm\) 5 \({}^{\circ}\) & 1035 \(\pm\) 46 \({}^{\circ}\) & 1055 \(\pm\) 13 \({}^{\circ}\) \\ ethylpyrazine & 1330 & 1341 & nutty, buttery & nd & rd & 57 \(\pm\) 4 \({}^{\circ}\) & 96 \(\pm\) 6 \({}^{\circ}\) & 135 \(\pm\) 8 \({}^{\circ}\) \\ 2-3-dimethylpyrazine & 1348 & 1356 & nutty, cocon & 137 \(\pm\) 8 \({}^{\circ}\) & 143 \(\pm\) 10 \({}^{\circ}\) & 213 \(\pm\) 19 \({}^{\circ}\) & 218 \(\pm\) 14 \({}^{\circ}\) & 247 \(\pm\) 13 \({}^{\circ}\) \\ _Furans_ & & & & & & & \\ _fururral_ & 1485 & 1499 & almond-like & 27,872 \(\pm\) 1390 \({}^{\circ}\) & 23,179 \(\pm\) 1833 \({}^{\circ}\) & 18,464 \(\pm\) 799 \({}^{\circ}\) & 18,203 \(\pm\) 1338 \({}^{\circ}\) & 17,712 \(\pm\) 1008 \({}^{\circ}\) \\ \hline \hline \multicolumn{7}{l}{\({}^{\star}\) Retention indexes from literature, phenotypes,org for DB-WAX, \({}^{\circ}\) Calculated retention index values relatively to the n-silamate ladder \(\rm nd-not\) detected in analyzed samples. Values are means \(\star\) standard deviation (\(n=3\)). Values in each column with different small superscript letters are significantly different (\(p<0.05\)).} \\ \end{tabular}
\end{table} 
Table 3: Volatile compounds identified in control biscuits (CB), prey-buckwheat biscuits (RBB) and in biscuits with increasing rutin addition (RBB-L, RBB-M, RBB-H, respectively). The compounds were identified by comparing its mass spectrum and RI with standard compounds. Results are expressed as \(\rm ng\,s^{-1}\,DW\). **Aldehydes and ketones**. The 2-methylpropanal and 3-methylbutanal are the volatile MRPs, formed via compounds of Strecker degradation. The content of 3-methylbutanal significantly increased in RBB and RBB-H samples (\(p<0.05\)). The amount of 2-methylpropanal increased after buckwheat flour substitution but then decreased in RBB-H (\(p<0.05\)). The amount of 2-methylpropanal is almost 12-times higher than in sponge cake [1]. It may be due to the fact that in our recipe we used a high amount of butter instead of oil. It is known that 3-methylbutanal is responsible for malty aroma of buckwheat honey. Another aldehyde that has been found in the volatile profile of rye-buckwheat biscuits was (E)-cinnamonaldehyde. It can be considered that cinnamon from spice mix is a main source of (E)-cinnamonaldehyde in biscuits and is responsible for their pleasant sweet aroma [29]. The concentrations of pentanal were considerably greater in samples with rutin supplementation. The peaks of pentanal were observed to be double the height in RBB-H, in comparison to control (\(p<0.05\)). [PERSON] et al.