## 2 Dataset Description  
The wine grape berries considered in the present work are from a Portuguese native variety, Touriga Franca (_Vitis vinifera_ L.), which is widely used to produce Port wine in one of the oldest appellation regions of the world, the Portuguese Douro region. This variety was chosen due to its high importance for our industrial partner, Symington Family Estates (www.symington.com), which is one of the world's largest producers of Port wine. A total of 240 bunches, 24 per day, were harvested from Quinta do Bomfim, Pinhao-Portugal, between the beginning of veraison (end of July) and maturity (end of September). The 24 bunches were collected at three different locations inside the vineyard with small, medium, and large vigor and at two different sun exposition levels. Then, line-scan hyperspectral image acquisition was performed in our laboratory-based imaging system using the fresh grape samples. Each sample measured by hyperspectral imaging was composed of six grape berries randomly collected from a single bunch with their  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Ref.**} & \multirow{2}{*}{**Methods**} & \multirow{2}{*}{**Preprocessing**} & \multicolumn{4}{c}{**RMSE**} \\ \cline{3-6}  & & & **Sugar (\({}^{\circ}\)Brix)** & **pH** & **Anthocyanin** \\ \hline \multirow{2}{*}{[7] a  & PLS & Normalization & 0.940–1.340 & - & - \\  & ANN & & 0.960–1.360 & & & \\ \hline \multirow{2}{*}{[8]} & \multirow{2}{*}{MPLS 1  & Raw & 1.370 & - & \\  & & MSC & 1.610 & 0.180 & - \\  & & SNV & 1.890 & - & \\ \hline \multirow{4}{*}{[9]} & \multirow{4}{*}{PLS  & Raw & & & 0.015 mg.g\({}^{-1}\) \\  & & SG & & & 0.013 mg.g\({}^{-1}\) \\  & & SNV & & & 0.013 mg.g\({}^{-1}\) \\  & PLS & SNV & - & - & 0.022 mg.g\({}^{-1}\) \\  & & MSC & & & 0.041 mg.g\({}^{-1}\) \\  & & 2 nd derivative & & & 0.028 mg.g\({}^{-1}\) \\  & PLS + SVM 2  & SG & - & - & 0.005 mg.g\({}^{-1}\) \\ \hline \multirow{4}{*}{[10]} & \multirow{4}{*}{PLS  } & MSC & 1.150 & - & - \\  & & SNV & 1.380 & & 13.560 cg.kg\({}^{-1}\) \\  & PCR 3  & MSC & 1.630 & - & - \\  & SNR & SNV & 1.410 & & 13.660 cg.kg\({}^{-1}\) \\  & MLR 4  & SNV & 1.530 & - & 17.980 cg.kg\({}^{-1}\) \\ \hline \multirow{4}{*}{[11]} & \multirow{4}{*}{PLS} & Raw & 0.650 & 0.050 & - \\  & & Normalization & 0.870 & 0.050 & 74.670 mg.L\({}^{-1}\) \\  & & SG & 0.650 & 0.050 & - \\  & & SNV & 1.830 & 0.080 & - \\ \hline \multirow{4}{*}{[13]} & ANN & Normalization & 0.950 & 0.180 & 14.000 mg.L\({}^{-1}\) \\ \hline \multirow{4}{*}{[14] a  } & ANN & Normalization & - & 0.170–0.190 & 22.100–51.300 mg.L\({}^{-1}\) \\ \hline \multirow{4}{*}{[12] a  } & SVM 2  & Normalization & 0.800–1.410 & 0.140–0.190 & 11.750–18.020 mg.L\({}^{-1}\) \\ \hline \multirow{4}{*}{[15] b  } & PLS &
\begin{tabular}{c} SG (1 st and 2 nd derivative) \\ \end{tabular} & 1.270–2.160 & - & - \\ \hline \multirow{4}{*}{[16]} & \multirow{4}{*}{MPLS} & 1 st derivative & - & 0.170 & \multirow{4}{*}{-} \\  & & 2 nd derivative & 1.690 & - & \\  & LOCAL & 1 st derivative & - & 0.150 & \\  & 2 nd derivative & 1.320 & - & \\ \hline \multirow{4}{*}{[17]} & PLS & \multirow{4}{*}{SG} & - & - & 0.160 mg.g\({}^{-1}\) \\  & PLS-ANN & & & 0.18 mg.g\({}^{-1}\) \\ \hline \multirow{4}{*}{[18] b  } & PLS & - & - & - & 1.510 mg.g\({}^{-1}\) \\ \cline{1-1} \cline{3-6}  & & & & & \\ \hline \end{tabular}
\end{table}
Table 1: Summary of most published works for predicting enological parameters using spectroscopic measurements in reflectance mode.  
pedicl attached, resulting in a total of 240 samples. After imaging and before conventional analysis, the samples were frozen at \(-18\)\({}^{\circ}\)C.