Pectins

Pectins are a group of natural polysaccharides found in plant cell walls, with the majority being homogalacturonan rich in alpha-(1→4)-D-galacturonic acid. They also include branched rhamnogalacturonan regions and neutral sugars. Pectins play a structural role in plants and have properties that enable gelation, thickening, and stabilization in foods and other products.

The gelling behavior depends on the degree of esterification (DE). High-methoxyl pectin (high methoxyl, DE > 50%) gels in the presence of high sugar and low pH; low-methoxyl pectin (DE < 50%) forms gels with divalent cations like calcium, often without high sugar.

Commercial pectin is extracted from citrus peel and apple pomace, and sometimes from other citrus or stone fruits. Extraction uses hot dilute acid, then purification and drying to produce powder or liquid pectin.

In food, pectins are used as gelling agents in jams and jellies, thickeners in beverages and dairy products, and as stabilizers and fat replacers. They are also a source of dietary fiber in functional foods.

Pectin is generally regarded as safe and is approved for use in many jurisdictions. As a soluble fiber, it is digested slowly and can affect texture and sweetness. High intake may cause gas or bloating in some individuals.