What gelatin-like carbohydrate obtained from certain fruits is used to thicken jams and jellies?

Pectin is a naturally occurring gelatin-like carbohydrate that is predominantly found in the cell walls of fruits. It plays a crucial role in the gelling process for jams and jellies, where it acts as a thickening and stabilizing agent. When fruits are cooked, the heat breaks down cell walls and releases pectin, which, in the presence of sugar and acid, forms a gel-like consistency as it cools. This property is essential for achieving the desired texture in preserves.

Agar, gelatin, and xanthan gum, while all capable of thickening or gelling, are derived from different sources and have distinct properties. Agar is derived from red algae, gelatin comes from animal collagen, and xanthan gum is a polysaccharide produced by fermentation. None of these are typically used in traditional fruit-based jams and jellies in the same way that pectin is. Thus, pectin is the most suitable and widely used ingredient for creating the ideal consistency in such confections.