Pectic substance including protopectin, pectinic acid and peptic acid are an important constituent of plant tissue and are found mainly in the primary cell wall.
They are also occur between cell walls, where they act as intercellular cement.
Upon mild hydrolysis, this substance yields water-soluble pectin, which can form gels or viscous colloidal suspension with sugar and acid.
The various pectic substances may influence texture of vegetables and fruits in several ways.
Pectic acid is the simplest of the pectic substances. The molecule is polyuronide, composed of galacturonic acid units combined by alpha-1,4-g;ycosidic linkages. Pectic acid is soluble in water and contains an abundance of carbonyl (-COOH) groups making it acidic and capable of forming water soluble salts.
Pectic substance
