# Prediction of Phytochemical Constituents in Cayenne Pepper Using MIR and NIR Spectroscopy
## 4 Discussion
This indicated that the infrared spectroscopy methods used in this study were unable to accurately discriminate between high or low levels of antioxidant capacity of chili samples. Prediction of antioxidant capacity (as measured by either of these methods) does not appear to have \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Study** & **Chili Type** & **DM Content** & **TPC** & **FRAP** & **CUPRAC** \\ \hline \multicolumn{2}{c}{_NIR spectroscopy_} & & & & \\ \hline \multirow{2}{*}{Present study} & \multirow{2}{*}{Green cayenne} & \(\mathrm{R^{2}_{pred}=0.74}\), & \(\mathrm{R^{2}_{pred}=0.65}\), & \(\mathrm{R^{2}_{pred}=0.71}\) & \(\mathrm{R^{2}_{pred}=0.73}\), \\  & & RMSEP = 464 & RMSEP = 70 & RMSEP = 512 \\  & & \(\mathrm{mg/100\ g}\) & \(\mathrm{mg/100\ g}\) & \(\mathrm{mg/100\ g}\) & \(\mathrm{mg/100\ g}\) \\ \hline \multirow{2}{*}{[PERSON], et al. [21]} & Bell pepper & \(\mathrm{R^{2}_{CV}=0.62}\), & & & \\  & (various) & RMSECV = 0.66\% & & & \\ \hline \multirow{2}{*}{[PERSON], et al. [6]} & Bell pepper & \multirow{2}{*}{} & \(\mathrm{R^{2}_{CV}=0.71}\), & \multirow{2}{*}{} & \\  & (various) & & RMSECV = 104 & & \\  & & & mg/100 g & & \\ \hline \multirow{2}{*}{[PERSON], et al. [10]} & Bell pepper & \(\mathrm{R^{2}_{CV}=0.93}\), & \multirow{2}{*}{} & \multirow{2}{*}{} & \\  & (various) & RMSECV = 0.4 & & & \\ \hline \multirow{2}{*}{[PERSON], et al. [12]} & Bell pepper & \(\mathrm{R^{2}_{CV}=0.53}\), & \(\mathrm{R^{2}_{CV}=0.67}\), & \multirow{2}{*}{} & \\  & (various) & RMSECV = 0.63\% & & RMSECV = 44 & \\ \hline \multirow{2}{*}{[PERSON], et al. [38]} & Habanero & \(\mathrm{R^{2}_{CV}=0.65}\), & \(\mathrm{R^{2}_{CV}=0.21}\), & \(\mathrm{R^{2}_{CV}=0.27}\), & \\  & & RMSECV = 162 & RMSECV = 38 & \\  & & mg/100 g & \(\mathrm{mg/100\ g}\) & & \\ \hline \multirow{2}{*}{[PERSON], et al. [39]} & Green cayenne & \(\mathrm{R^{2}_{pred}=0.85}\), & \multirow{2}{*}{} & \multirow{2}{*}{} & \\  & & RMSEP = 0.61\% & & & \\ \hline \multicolumn{2}{c}{_MIR spectroscopy_} & & & & \\ \hline \multirow{2}{*}{Present study} & \multirow{2}{*}{Green cayenne} & \(\mathrm{R^{2}_{pred}=0.54}\), & \(\mathrm{R^{2}_{pred}=0.86}\), & \(\mathrm{R^{2}_{pred}=0.96}\), & \(\mathrm{R^{2}_{pred}=0.99}\), \\  & & RMSEP = 0.51\% & \(\mathrm{RMSEP}=433\) mg & \(\mathrm{RMSEP}=96\) & RMSEP = 478 \\  & & \(\mathrm{TE/100\ g}\) & \(\mathrm{mg/100\ g}\) & \(\mathrm{mg/100\ g}\) \\ \hline \multirow{2}{*}{[PERSON], et al. [38]} & [PERSON] & \(\mathrm{R^{2}_{CV}=0.28}\), & \(\mathrm{R^{2}_{CV}=0.37}\), & \(\mathrm{R^{2}_{CV}=0.40}\), & \\  & & RMSECV = 145 & RMSECV = 35 & \\  & & \(\mathrm{mg/100\ g}\) & \(\mathrm{mg/100\ g}\) & & \\ \hline \multirow{2}{*}{[PERSON], et al. [19]\({}^{1}\) Study was performed on the ground, freeze-dried powder.} & \multirow{2}{*}{[PERSON]} & \(\mathrm{R^{2}_{CV}=0.94}\), & \multirow{2}{*}{} & \\  & & & & \(\mathrm{SEP}=0.02\) mg & \\ \multicolumn{2}{c}{} & & & \(\mathrm{GAE/100\ g}\) & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Summary of the results for the prediction of DM, TP, FRAP, and CUPRAC content in green cayenne pepper and their comparison to previous studies on other chili varieties. Note: \(\mathrm{R^{2}_{pred}}\) and RMSEP values are provided where reported; \(\mathrm{R^{2}_{CV}}\) and RMSECV values are provided where a test set was not analyzed. been previously attempted in this crop in the literature; however, the DPPH method has been used [23]. While these authors reported some success, the results are not directly comparable to either the FRAP or CUPRAC assays.