The basic principle used to extract pectin is to decompose the original pectin (in the form of protopectin, pectinic acids, and pectinates) into water-soluble pectin and then separate it from the cellulose, starch, protein, colors, and other components.

Acid extraction
Acidic, enzymatic, and microbiological manufacturing processes are used to extract pectin. The acid extraction method is the commonly used method.

Mineral acids (such as hydrochloric acid, sulfuric acid) or organic acids (e.g. citric acid) are employed to hydrolyze the original pectin into water-soluble pectin, and then obtain crude pectin by ethanol precipitation or metal salt precipitation.

Ethanol precipitation
Ethanol precipitation is occupied as pectin is insoluble in isopropyl alcohol, ethanol and other organic solvents. And follows drying, milling and standardization (usually with sugar).

Enzymatic processing
Enzymes such as esterases, polygalacturonases, and pectin lyases are often used to facilitate the hydrolysis of pectin to different degrees of esterification or polymerization.

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