# Extraction, Characterization, and Applications of Pectins from Plant By-Products
## 3 Pectin Extraction Methods
### Traditional Methods for the Pectin Extraction
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Pectin Sources**} & \multicolumn{6}{c}{**Extraction Conditions**} & \multirow{2}{*}{**Yield (\%)**} & \multirow{2}{*}{**DM (\%)**} & \multirow{2}{*}{**GaLA (\%)**} & \multirow{2}{*}{**Reference**} \\ \cline{2-2} \cline{5-10}  & **Treatments** & & & & & & & & & & \\ \hline Papaya peel & CHE & HCl & 80 \({}^{\circ}\)C & 2.0 & 1:50 & 60 min & 16 & 53.4 & 70.5 & - & [60] \\ \hline Potato pulp & CHE & citric acid & 90 \({}^{\circ}\)C & 2.04 & 1:15 & 60 min & 14.34 & 37.45 & 24.3 & 320 & [39] \\ \hline Carrot & \multirow{2}{*}{CHE} & \multirow{2}{*}{-} & \multirow{2}{*}{90 \({}^{\circ}\)C} & \multirow{2}{*}{1.3} & \multirow{2}{*}{-} & 79.8 & \multirow{2}{*}{15.2} & 45.2 & 75.5 & - & [61] \\ \cline{2-2} \cline{5-10}  & & & & & & & & & & \\ \hline Lime peel & CHE & HCl & 95 \({}^{\circ}\)C & - & 1:40 & 1 h & 15.91 & 78.49 & 89.8 & 794.7 & [40] \\ \hline Ponkan peel & CHE & HNO\({}_{3}\) & - & 1.6 & 1:36 & 100 min & 25.6 & 85.7 & 84.5 & 80.6 & [62] \\ \hline Chicory & CHE & - & 80 \({}^{\circ}\)C & 1.5 & 1:20 & 1 h & 12.2 & 44.7 & 71.9 & 260 & [63] \\ \hline Sugar beet & \multirow{2}{*}{CHE} & \multirow{2}{*}{-} & \multirow{2}{*}{80 \({}^{\circ}\)C} & \multirow{2}{*}{1.5} & \multirow{2}{*}{1:20} & \multirow{2}{*}{1 h} & \multirow{2}{*}{7.1} & \multirow{2}{*}{46.4} & \multirow{2}{*}{66.2} & \multirow{2}{*}{651} & [63] \\ pulp & & & & & & & & & & \\ \hline Green tea & \multirow{2}{*}{CHE} & \multirow{2}{*}{water} & \multirow{2}{*}{80 \({}^{\circ}\)C} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{3 h} & \multirow{2}{*}{5.3} & \multirow{2}{*}{26.5} & \multirow{2}{*}{32.4} & \multirow{2}{*}{276} & [64] \\ leaf & & & & & & & & & & \\ \hline Green tea & \multirow{2}{*}{CHE} & \multirow{2}{*}{HCl} & \multirow{2}{*}{60 \({}^{\circ}\)C} & \multirow{2}{*}{2} & \multirow{2}{*}{-} & \multirow{2}{*}{3 h} & \multirow{2}{*}{6.1} & \multirow{2}{*}{21.1} & \multirow{2}{*}{31.8} & \multirow{2}{*}{396} & [64] \\ leaf & & & & & & & & & & \\ \hline Apple & \multirow{2}{*}{CHE} & \multirow{2}{*}{NaoH} & \multirow{2}{*}{60 \({}^{\circ}\)C} & \multirow{2}{*}{8} & \multirow{2}{*}{-} & \multirow{2}{*}{3 h} & \multirow{2}{*}{9.2} & \multirow{2}{*}{24.7} & \multirow{2}{*}{41.6} & \multirow{2}{*}{334} & [64] \\ pomace & & & & & & & & & & \\ \hline Pomergranate & \multirow{2}{*}{CHE} & \multirow{2}{*}{HNO\({}_{3}\)} & \multirow{2}{*}{90 \({}^{\circ}\)C} & \multirow{2}{*}{1.5} & \multirow{2}{*}{1:25} & \multirow{2}{*}{70} & \multirow{2}{*}{25.3} & \multirow{2}{*}{41.7} & \multirow{2}{*}{84.5} & \multirow{2}{*}{142} & [65] \\ peel & & & & & & & & & & \\ \hline Apple & \multirow{2}{*}{CHE} & \multirow{2}{*}{HNO\({}_{3}\)} & \multirow{2}{*}{86 \({}^{\circ}\)C} & \multirow{2}{*}{1.7} & \multirow{2}{*}{1:20} & \multirow{2}{*}{80 min.} & \multirow{2}{*}{8.5} & \multirow{2}{*}{75} & \multirow{2}{*}{62.0} & \multirow{2}{*}{549} & [66] \\ pomace & & & & & & & & & & & \\ \hline Apple & \multirow{2}{*}{CHE} & \multirow{2}{*}{HNO\({}_{3}\)} & \multirow{2}{*}{BT} & \multirow{2}{*}{-} & 1:40 & 10 min & 15.04 & 72.29 & 57.28 & - & [67] \\ pomace & & & & & & & & & & & \\ \hline Graperuit & \multirow{2}{*}{CHE} & \multirow{2}{*}{HCl} & \multirow{2}{*}{80 \({}^{\circ}\)C} & \multirow{2}{*}{1.5} & \multirow{2}{*}{1:50} & \multirow{2}{*}{1.5 h} & \multirow{2}{*}{-} & \multirow{2}{*}{69.03} & \multirow{2}{*}{68.36} & \multirow{2}{*}{385.5} & [68] \\ peel & & & & & & & & & & \\ \hline Jackfruit & \multirow{2}{*}{CHE} & \multirow{2}{*}{distilled & \multirow{2}{*}{water} & \multirow{2}{*}{90 \({}^{\circ}\)C} & \multirow{2}{*}{-} & \multirow{2}{*}{1:25} & \multirow{2}{*}{1 h} & \multirow{2}{*}{14.59} & \multirow{2}{*}{-} & \multirow{2}{*}{72.62} & - & [69] \\ finds & & & & & & & & & & \\ \hline Watermelon & \multirow{2}{*}{PEel} & \multirow{2}{*}{CHE} & \multirow{2}{*}{H\({}_{5}\)SO\({}_{4}\)} & \multirow{2}{*}{90 \({}^{\circ}\)C} & \multirow{2}{*}{1.0} & \multirow{2}{*}{1:20} & \multirow{2}{*}{150 min} & \multirow{2}{*}{17.6} & \multirow{2}{*}{41.2} & \multirow{2}{*}{78.3} & \multirow{2}{*}{119} & [70] \\ peel & & & & & & & & & & \\ \hline \hline \end{tabular} \(\mathbb{S}/L\): solid-liquid ratio. DM: degree of methyl esterification. GalA: galacturonic acid content. Mw: molecular weight. CHE: conventional heating extraction. BT: boiling temperature.  
\end{table}