Stevia

Better understanding stevia

Stevia, stevia rebaudiana, from the Asteraceae family, is native to the Paraguay region. It is a shrub that grows wild in the meadows covering valleys and mountain plateaus under a tropical climate.

To meet the demand of the global sweetener market, stevia cultivation initially expanded to South America, especially Brazil, then to Central America, then to Japan and China as well as the rest of Asia. Today, the leading producer of stevia is China.

Ethnobotanists trace the use of Stevia back 2000 years in the culinary practices of the indigenous peoples of this region. It was used to sweeten foods and was capable of softening the flavour of certain preparations. For example, to neutralise the bitterness of mate, their favourite drink.

Stevia is a shrub about 50 cm tall, which can reach 1 m. It is the leaves that are harvested for their sweetening power.
Harvesting takes place at the end of summer, when the concentration of sweet molecules (rebaudioside A) is at its maximum. Stevia thrives in the sun but fears drought because its roots are near the surface and not deep.
It reproduces by germination but has a low germination rate; therefore, cuttings are used but this poses a labour problem.
Once harvested, the leaves are dried before being ground into powder to extract the rebaudioside.

Stevia leaves contain several glycosides with sweetening power that represent 5 to 20% of their dry weight depending on growing conditions: stevioside A, rebaudioside E, dulcoside A.

It is rebaudioside A that has the highest sweetening power, 300 times more than saccharose. This plant has shown potential for treating obesity and hypertension, moreover it has a negligible effect on the increase of blood glucose and has even demonstrated an ability to reduce glucose intolerance.
It can therefore provide a sweetener compatible with diabetic diets and hypoglycaemic diets.