Licorice, the root of Glycyrrhiza glabra , Fabaceae or Leguminosae, contains a saponic glycoside called glycyrrhizin. This is used to flavor pharmaceuticals, candy and tobacco. The miracle fruit, Synsepalum dulciferum , Sapotaceae, contains a protein that causes sour substances to taste sweet. Serendipity berries, Dioscoreophyllum cumminsii , Menispermaceae, contain an intensely sweet protein. Starch As mentioned above, sugar in plants is converted to starch.
All plants contain starch also.
Again, which plants are important for starches depends on a number of economic factors. Starch is widely used for sizing textiles and paper, coating paper, in rubber and plastics, chewing gum, candy, adhesives, laundry starch, some paints, detergents, etc. Large amounts are used to make high fructose corn syrup. Starch is common in many of our food plants. We already talked about potatoes, corn, cassava, etc.