## 3 Results
### Changes upon Aroma Release after Roasting  
Roasted green tea (Hojicha) has a characteristic and appreciated roasty flavor due to the formation of alkylpyrazines, stable products of the Maillard reaction. Nevertheless, the roasting process must avoid high levels of acrylamide formation, catechin degradation \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**VFC** & \multicolumn{2}{c}{**\% Recovery (\(\pm\)CV%)**} & \multicolumn{2}{c}{**Precision (CV%)**} \\ \hline \multicolumn{5}{c}{**Standard Addition (ug/mL)**} \\ \hline  & 1.0 & 5.0 & 20.0 & Intra-day & Inter-day \\ \hline
2,4-heptadienal & 86.18 (\(\pm\)9.06) & 85.10 (\(\pm\)10.92) & 88.70 (\(\pm\)7.73) & 4.58 & 8.42 \\ \(\beta\)-damascenone & 82.25 (\(\pm\)10.05) & 79.08 (\(\pm\)9.77) & 82.02 (\(\pm\)11.23) & 9.71 & 10.37 \\ \(\beta\)-ionone & 88.45 (\(\pm\)8.15) & 87.65 (\(\pm\)7.85) & 87.98 (\(\pm\)9.05) & 3.12 & 6.98 \\ \(\mathrm{Linalool}\) & 90.08 (\(\pm\)7.12) & 93.44 (\(\pm\)6.76) & 94.13 (\(\pm\)5.26) & 3.60 & 8.67 \\ \(\mathrm{I}\)ode & 89.16 (\(\pm\)4.08) & 93.21 (\(\pm\)5.26) & 91.09 (\(\pm\)4.78) & 9.76 & 8.25 \\ \(\mathrm{I}\)-ethyl-\(\mathrm{pyrazine}\) & 95.08 (\(\pm\)7.35) & 94.99 (\(\pm\)6.12) & 95.76 (\(\pm\)6.06) & 4.57 & 5.01 \\ \(\mathrm{I}\)-ethyl-\(\mathrm{pyrazine}\) & 97.05 (\(\pm\)9.10) & 94.55 (\(\pm\)3.47) & 96.43 (\(\pm\)5.12) & 6.14 & 8.04 \\ \(\mathrm{I}\)-ethyl-\(\mathrm{3}\),\(\mathrm{6}\)-dimethyl\(\mathrm{pyrazine}\) & 91.21 (\(\pm\)6.35) & 90.35 (\(\pm\)3.30) & 93.00 (\(\pm\)4.58) & 4.01 & 8.53 \\ \(\mathrm{I}\)-ethyl-\(\mathrm{3}\),\(\mathrm{5}\)-dimethyl\(\mathrm{pyrazine}\) & 98.75 (\(\pm\)7.21) & 98.54 (\(\pm\)8.01) & 98.31 (\(\pm\)8.65) & 7.15 & 5.98 \\ \(\mathrm{I}\) acetyl-\(\mathrm{pyrazine}\) & 96.01 (\(\pm\)10.01) & 96.83 (\(\pm\)8.03) & 99.17 (\(\pm\)8.28) & 3.21 & 5.63 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Accuracy data from recovery experiments (n = 3) and precision data (intra-day precision, n = 6, inter-day precision, n = 18). \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**VCF** & \multicolumn{2}{c}{**Water**} & \multicolumn{2}{c}{**Green Tea**} \\ \hline  & **Slope (\(\pm\)sd)** & **r2** & **LOQ (\(\mu\)g/mL)** & **Slope (\(\pm\)sd)** & **r2** \\ \hline
2,4-heptadienal & 14.2 (\(\pm\)1.6) & 0.986 & 0.005 & 11.4 (\(\pm\)0.9) & 0.986 \\ \(\beta\)-damascenone & 1.0 (\(\pm\)0.2) & 0.987 & 0.008 & 1.1 (\(\pm\)0.5) & 0.981 \\ \(\beta\)-ionone & 7.4 (\(\pm\)0.9) & 0.995 & 0.037 & 7.9 (\(\pm\)1.2) & 0.989 \\ \(\mathrm{Linalool}\) & 11.1 (\(\pm\)1.9) & 0.999 & 0.031 & 10.1 (\(\pm\)1.5) & 0.996 \\ \(\mathrm{Indole}\) & 12.7 (\(\pm\)1.5) & 0.998 & 0.009 & 11.6 (\(\pm\)2.0) & 0.994 \\ \(\mathrm{2}\)-ethyl-\(\mathrm{6}\)-methyl-\(\mathrm{pyrazine}\) & 8.9 (\(\pm\)0.8) & 0.994 & 0.010 & 9.8 (\(\pm\)1.0) & 0.989 \\ \(\mathrm{2}\)-ethyl-\(\mathrm{5}\)-methyl-\(\mathrm{pyrazine}\) & 9.3 (\(\pm\)1.4) & 0.994 & 0.011 & 11.7 (\(\pm\)1.9) & 0.991 \\ \(\mathrm{2}\)-ethyl-\(\mathrm{3}\),\(\mathrm{6}\)-dimethyl-\(\mathrm{pyrazine}\) & 7.5 (\(\pm\)1.9) & 0.998 & 0.032 & 9.3 (\(\pm\)0.8) & 0.989 \\ \(\mathrm{2}\)-ethyl-\(\mathrm{3}\),\(\mathrm{5}\)-dimethyl\(\mathrm{pyrazine}\) & 7.2 (\(\pm\)1.2) & 0.997 & 0.040 & 8.5 (\(\pm\)1.3) & 0.988 \\ \(\mathrm{acetyl}\)-\(\mathrm{pyrazine}\) & 8.4 (\(\pm\)1.3) & 0.999 & 0.023 & 9.0 (\(\pm\)0.9) & 0.989 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Linearity data (n = 3). Linear concentration range 0.02–2.0 ug/mL. and significant changes in the VFC content. To this end, it is necessary to optimize the roasting procedure, as was performed by [PERSON] et al. (2008) [PERSON] et al. (2008).