The fruit known for being a natural source of pectin is the apple. Pectin is a soluble fiber primarily found in the cell walls of fruits, and apples contain a significant amount of it, especially in their skins. Pectin is widely used in cooking and food processing for making jams, jellies, and preserves, as it helps in gelling. Other fruits such as citrus and quinces also contain pectin, but apples are the most commonly recognized source. This natural thickening agent is appreciated for its ability to achieve the desired consistency in various recipes.