Saponins (Latin "sapon", soap + "-in", one of) are bitter-tasting usually toxic plant-derived secondary metabolites, being organic chemicals, that have a foamy quality when agitated in water and a high molecular weight. They are present in a wide range of plant species throughout the bark, leaves, stems, roots and flowers but found particularly in soapwort (genus Saponaria), a flowering plant, the soapbark tree (Quillaja saponaria), common corn-cockle (Agrostemma githago L.), baby's breath (Gypsophila spp.) and soybeans (Glycine max L.). They are used in soaps, medicines (e.g. drug adjuvants), fire extinguishers, as dietary supplements, for synthesis of steroids, and in carbonated beverages (for example, being responsible for maintaining the head on root beer). Saponins are both water and fat soluble, which gives them their useful soap properties. Some examples of these chemicals are glycyrrhizin (licorice flavoring) and quillaia (alt. quillaja), a bark extract used in beverages.[1][2][3]