Pectin is a natural carbohydrate, specifically a heteropolysaccharide, found in the cell walls and middle lamellae of terrestrial plants, especially abundant in fruits such as apples, citrus fruits, plums, and quince. Chemically, it is made up mainly of the sugar acid galacturonic acid with some rhamnose, and it has a complex branched structure. In plants, pectin acts as a structural fiber that helps hold adjacent cell walls together, giving fruits their firmness and shape as they ripen. As fruits over-ripen, pectin breaks down into simpler sugars, which makes the fruit soften. Commercially, pectin is extracted primarily from citrus peels and is used as a gelling agent and thickener. It is a key ingredient in making jams, jellies, preserves, and some dessert fillings, providing the gel-like texture when combined with sugar and acid. Pectin is also used as a food stabilizer in juices and dairy drinks and as a source of dietary fiber. Pectin is available commercially in powder or liquid form and is also used as a soluble fiber supplement due to its health benefits, such as aiding digestion and lowering cholesterol. Modified forms of pectin can be used in medications as well. In short, pectin is a plant-derived fiber that acts as a natural glue in plants and as a thickening and gelling agent in food and other products. It is vegan and widely utilized in food production and dietary supplements.