Description and geographic origin :
A small shrub that can reach 40 to 60 cm and sometimes up to 1 m in height, Stevia blooms all year in tropics and from August to September in our latitudes. This plant is native from Paraguay, from a region called the Amambay in the middle subtropical forest in the south-east. This area is very mountainous and somewhat isolated which may explain why the Stevia has been so long ignored in European countries.
The Guarani Indians living in this region the Amambay have used for centuries the species Stevia rebaudiana in nutrition and medicine. They called it "ka'a he'e", which means "sweet grass" and used it to sweeten the bitter mate (local tea). It was first described in 1899 by the Swiss scientist, Dr Moisés Santiago Bertoni:
"When observing this plant, nothing in particular attracted the attention, but when even a small piece of leaf is placed in the mouth, one is impressed with its sweetness."
Sweetening Power :
Stevia gets its sweetness from a family of molecules called "Steviol glycosides". The members of this family of molecules, among which the most known are the Stevioside and Rebaudioside A, that have a natural sweetness ranging from 60 to 350 times that of sucrose are not fermentable, indigestible, and therefore have almost zero calories and a glycemic index of almost zero.
Steviol glycosides : sweetening power compared to sucrose *
- Stevioside : 250 to 300
- Rebaudioside A : 300 to 450
- Rebaudioside C (or dulcoside B) : 60 to 120
- Dulcoside A : 60 to 120
- Rebaudioside B : 300 to 350
- Rebaudioside D : 250 to 400
- Rubusoside : about 200
- Steviolbioside : 100 to 125
* Reference : "La Stevia et les glycosides de steviol" of Jan M.C. Geuns