PLANT OF THE WEEK

Dr. T. Ombrello - UCC Biology Department

STEVIA

Common names:  Stevia,  Kaa he-he (Sweet Herb),  Honey Yerba,  Yerba Dulce, Sweet Leaf  

Scientific  name:        Stevia rebaudiana

Explanation of scientific name:       

Stevia - Named for Dr. Peter James Esteve, a Spanish botanist who died in 1566.

rebaudiana - Named for Dr. Rebaudi, a Paraguayan chemist who was the first person to        

                     extract the compound that makes the plant’s leaves and stems so sweet.

Most Americans have never heard of Stevia rebaudiana, but that is changing. The plant is the source of stevioside, a sweet, crystalline glycoside that is about 300 times sweeter than table sugar (sucrose) but with essentially no calories. Stevioside (commonly called simply stevia) has been controversial. In our country the Food and Drug Administration (FDA) long did not approved its use as a food additive, citing concerns about the safety of the sweetener for human use. It was considered an “unsafe food additive” under the Food, Drug and Cosmetic Act. Prior to 1991, however, Celestial Seasonings offered an herbal tea with stevia as an ingredient.  In 1995 the FDA allowed stevia to be sold as a “dietary supplement.” Dietary supplements are not as rigorously regulated, and are controlled by the Health and Education Act. So, stevia was not found in typical supermarket food products, but it could be purchased in health food stores and other outlets. It was marketed as dried leaves, liquid concentrates, powders, and pills. In 2008 the FDA declared that stevia was safe in foods and beverages. The United States will see numerous companies incorporate it into their products, since there is considerable consumer interest in natural, low or no calorie sweeteners.

Stevia rebaudiana is an herbaceous annual plant, native to Paraguay, South America. It belongs to the large Sunflower family of plants (Asteraceae) and counts as its close relatives daisies and chrysanthemums. Stevia’s white flowers, however, are small and not particularly showy. There are 150 species of Stevia. All are native to South and North America, but only Stevia rebaudiana contains appreciable amounts of stevioside.

As early as the 16^th century Spanish explorers noted that the indigenous peoples of Paraguay were utilizing the plant to sweeten drinks and medicines. But it was not until the 19^th century that the plant was seriously investigated by scientists. Dr. Moises Santiago Bertoni is credited with bringing it to the attention of the outside world during his studies of herbs used as sweeteners by native peoples. In 1931 stevioside was identified by French chemists, and its use expanded. In the 1950’s Japan began growing the plant as a crop. Today it is the world’s largest user of stevia, with stevioside found in soft drinks (including Diet Coke), chewing gum, candy, ice cream, sweet pickles, soy sauce, bread, seafood, and prepared vegetables. Other countries with a history of using stevioside as a no calorie sweetener include China, South Korea, Taiwan, Israel, Brazil, Uruguay, Paraguay, Columbia, Thailand, Germany, and Malaysia.

Sugar substitutes, especially those with no calories, have long been of interest to people. Products such as aspartame (“Equal”) and saccharin (“Sweet-n-Low”) are produced in great quantities around the world, and especially in the United States. Some producers probably see stevia, a non patentable natural product, as competition to the lucrative artificial sweeteners now available. Other people probably see it as an alternative sweetener that deserves wider usage.