Rebaudioside A or reb A, the common stevia extract with the European food additive number E960. It is the most used steviol glycoside as a sugar substitute in food and beverage due to its high content in stevia leaves (accounts for 15-20% in total steviol glycosides) and with little bitterness.
Generally, the purifying rebaudioside A from a mixture of stevia glycosides of the stevia plant is similar with that of extracting stevioside.
The following brief manufacturing process of high purity Reb-A (98%) is from China manufacturer, Qufu Xiangzhou (1):
The leaves of stevia rebaudiana bertoni are first dried, crushed, and extracted in hot water. The extract is a dark solution containing stevia glycosides, along with impurities such as leaf pigments and pectin.
Treated the extract with ferric chloride and calcium oxide to precipitate impurities, and follow filtration. Passed the filtrate through an adsorption resin to trap the steviol glycosides.
Subsequently, wash the resin with ethanol to release steviol glycosides and then pass the ethanol extract through ion exchange resin for desalination, and then go through a decolorization process with activated carbon. Then follows the process of drying, concentration and decolorization. Finally, obtain rebaudioside A by spray drying.
As other stevia glycosides have very similar chemical structures – the same backbone steviol, so it is difficult to obtain high purity reb A.
|Stevia leaf extract, Stevia sweetener
A white to off-white hygroscopic powder or granular.
As a high intensity sweetener, about 300 times as sweet as sucrose, with less bitter and licorice off-tastes than stevioside.
From Merisant’s stability testing in 2008: Reb A will not degrade when stored at 105˚C for 96 hours, and it is almost stable in carbonated citric acid beverages and phosphoric acid beverages.
From Cargill’s stability testing in 2008: rebaudioside A is more stable in the pH 4 to 6 and at temperatures from 5˚C to 25˚C when used in beverages. (2)
Freely soluble in ethanol: water 50/50 (v/v), sparingly soluble in water (1.0%) and in ethanol.
They’re two major constituents in steviol glycosides, which differ from each other by the number of glucose moieties, stevioside has one less glucose moiety than reb-A.
Their main difference lies in the taste. Stevioside is about 200 times sweeter than sucrose, but with significant bitter taste at higher concentrations. Rebaudioside A is about 300 times as sweet as sucrose, with less bitter and licorice aftertaste.
Rebaudioside A is a natural sweetener that is widely used in sugar-free and reduced-calorie food & drink than stevioside due to its better quality of sweetness – minimal bitter aftertaste. With the increasing demand for sugar alternatives, natural sweeteners are more appealing to consumers than artificial ones.
Reb A is available in the end market in the form of solid or liquid. The former can be found in the PureVia packet, which is made of 99% Reb A and dextrose, also along with natural flavors (3). Another reb A solid brand is Truvia, which is sweetened with erythritol, a sugar alcohol used as a bulking agent to manage the high sweetness of reb A (4), the same function with dextrose in PureVia.
The following food may contain with reb A:
- Carbonated drinks
- Tabletop sweeteners
- Sweetened teas
- Fruit juice drinks
- Energy drinks
- Flavored water
What’re the benefits of Rebaudioside A?
- Zero calories
- No carbohydrate
- Does not raise blood glucose or insulin levels (Zero Index Glycemic), safe for people with diabetes
- Keto, Vegan, and Gluten-Free
High-purity (95% minimum) of individual or combined steviol glycosides can be considered as GRAS (Generally Recognized as Safe) by the FDA (6). For example, FDA had no questions regarding Guilin Layn’s conclusion that its reb A (≥97% by weight (w/w)) is GRAS as a table top sweetener and as a general purpose sweetener in foods, excluding meat and poultry products and infant formulas. (7)
Now you may have a knowledge of the high intensity sweetener – Rebaudioside A (E960), from the following aspects:
- Production process
- Difference with stevioside
What kinds of food labels have you found this ingredient in? Let me know in the comments.