Stevia
Stevia is a natural sweetener derived from the leaves of the Stevia rebaudiana plant. It has been used for centuries by indigenous peoples of Paraguay to sweeten teas and medicines and it’s become very popular for its natural origin and good taste. Stevia is renowned for its intense sweetness, often cited as being 200 to 300 times sweeter than sugar.
Stevia sweeteners are made by extracting steviol glycosides from a stevia plant’s leaves. Stevioside (bitter aftertaste) and rebaudioside A (superior sweetness, lack of a bitter aftertaste) are the two main steviol glycosides with the highest concentrations, compared with the others. Moreover, the glycosylated steviol glycosides and other enzyme-modified steviol glycosides have been developed to reduce the bitter aftertaste.
Source and Processing
Stevia is primarily grown in several countries, with major producers including China, Paraguay, Brazil, and Japan. China is the largest exporter of stevia extracts. The plant itself requires a warm, wet climate to thrive. To extract the sweet compounds, the leaves are harvested, dried, and steeped in water. The resulting liquid is then filtered and purified to obtain the steviol glycosides, which are the sweet components of Stevia
Main function in Confections
In confections, Stevia serves as a sugar substitute due to its intense sweetness. It is often used in sugar-free candies, chocolates, chewing gums, and other sweet treats. Stevia provides a way to create sweet products without the added calories of sugar, making it popular among those looking to reduce their sugar intake.
Molecular Structure
Stevia leaf is a composite of several sweet diterpene glycosides including stevioside, rebaudioside (A, B, C, D, and E) and dulcoside A, in which stevioside and rebaudioside A contributes to the sweetness and the sucrose-like sweetness of stevia respectively
Properties
- Solubility: Steviol glycosides, the compounds responsible for Stevia's sweetness, are soluble in water. This makes it easy to incorporate into beverages and liquid confections.
- Thermal Stability: Stevia is relatively stable at high temperatures (up to 80°C/176°F), making it suitable for cooking and baking. However, prolonged exposure to heat can sometimes lead to a slight bitter aftertaste.
- pH: Very stable at a wide range of pH (2-10) can be used in sour confections.
- Body Metabolism: One of the key advantages of Stevia is that it is not metabolized by the body. This means it has zero calories and does not raise blood sugar levels, making it a popular choice for diabetics and those on low-calorie diets.
Regulatory
- United States: Stevia and its sweetening compounds, specifically Rebaudioside A, have been granted Generally Recognized as Safe (GRAS) status by the Food and Drug Administration (FDA). Companies can use high-purity stevia extracts in foods and beverages.
- European Union: approved for use as a food additive in 2011. The EU has established an acceptable daily intake (ADI) for Steviol glycosides, the sweet compounds in Stevia, which specifies the amount that can be safely consumed on a daily basis
