Pectin, << PEHK tuhn, >> or pectinic acid, is a substance found in the cell walls of many fruits and some vegetables. Pectin binds cells to one another and provides firmness in the fruit or vegetable. It is used as a gelling agent in many processed foods and as a thickener in such foods as jelly, jam, preserves, and relish. Pectin provides dietary fiber but has no other nutritional value. It belongs to the carbohydrate group of foodstuffs, which includes starches and sugars.
The amount and type of pectin in a fruit depends on the species. Some fruits, including apples, currants, grapefruit, oranges, and plums, contain a large amount of the kind of pectin that causes gelling. When such fruits are cooked to make jelly or jam, the pectin forms a network of fibers that thicken the fruit juices. The pectin in other fruits, such as apricots, cherries, pineapples, and strawberries, does not cause these fruits to gel when they are cooked. However, commercial pectin can be added to thicken the mixture. Commercial pectin, available as a liquid or powder, is made from the rinds of apples and citrus fruits, especially lemons and oranges.
