Interest in Rebaudioside A, Rebiana, or Reb A, as it is commonly known, has grown exponentially with the recent notification from FDA that it has no objection to its GRAS status as a sweetener. Reb A, at a 95% level of purity or higher, was cleared by FDA in Dec. 2008.
This natural, zero-calorie sweetener has the potential to change the sweetener industry significantly. Reb A comes on to the market at a very opportune time in the United States. The national waistline has never been greater, so the need for a natural substitute to caloric and noncaloric sweeteners is well, natural. Here’s a look at what Reb A is, its regulatory status, how it’s derived and some technical background.
What is Reb A?
Reb A is a completely natural, high-intensity sweetener that is about 350 to 450 times sweeter than sugar. It’s found in nature in the leaf of the Stevia Rebaudiana plant, which is native to South America, and where it has been used safely as a sweetener for generations.
While Reb A is derived from the stevia plant, it is not the same as the stevia that has been sold for years in the U.S. as a dietary supplement. Reb A is one of several related sugar-like substances known as steviol-glycosides that are found in the stevia plant, as shown in Table 1. It is one of the sweetest and best-tasting steviol-glycosides.
The regulatory story
GRAS status follows submissions by various food and beverage manufacturers to the FDA, in which the companies had concluded that they had enough documented research information on their particular stevia derivatives to warrant GRAS status. It was already legal to import and grow stevia in the United States, and the sale and consumption of stevia is permitted as a dietary supplement on the basis of its low glycemic index.
Reb A was not previously approved for use in the United States and European Union (EU) due to two factors historically associated with conventional stevia extract. First, there was an issue with the taste profile of stevia—the crude extract that was used contains a mixture of approximately 10 different glycosides, not all of which taste good. Second, because the extract contains a mixture of different molecules, it was impossible to give a clear specification of the product. The ratio of molecules in the extract would vary substantially, depending on the climate and weather conditions where the stevia was grown. This variation caused difficulties for food and beverage manufacturers, and more importantly, made it difficult to conduct clinical trials to assess product safety.
These challenges were overcome by PureCircle, Florham Park, NJ, a company that pioneered research into the extraction and refinement of Reb A. The company developed proprietary process technologies to ensure its highly-purified Reb A has a good flavor profile and is a standardized product with standardized characteristics. This enabled clinical trials on the safety of the product to be complete.