Tannin is a biomolecule extracted from fruits and plants. It can be found in the seeds, stem tissues, roots, leaves, and bark of plants. Tannin is most commonly found in gymnosperm and angiosperm plants. It is known to protect plants from predation and aids in the synthesis of plant hormones. Fruits, such as oranges, grapes, walnuts, pecans, hazelnuts, strawberries, blueberries, and cranberries, are found to be rich in tannin.