How is stevia made?
What's in Truvia and Purevia
As stevia gains popularity in the marketplace, there’s much confusion about what really is a true stevia product and how much processing is involved.
Besides the actual plant, stevia is currently sold in three forms. As we go through them, remember that the actual stevia leaf contain 10 different parts.
1. Stevia sold as "Dietary Supplements". These can be labeled as:
- Stevia leaf
- S. rebaudiana
- Stevia Rebaudiana
- Stevia Rebaudiana Bertoni
Dietary supplements can only be sold in health food stores. Generally dietary supplements have more components of the leaf...but not always.
2. Stevia sold as a sweetener. Usually found in packaged foods and bevarages under the trade names:
- Rebaudioside A
- Rebiana A
- Reb A
These are made from 1/10th of the stevia leaf.
The FDA states this about Reb A products on its website (here): “These products are not Stevia. In general, Rebaudioside A differs from Stevia in that it is a highly purified product. Products marketed as “Stevia” are whole leaf Stevia or Stevia extracts of which Rebaudioside A is a component.”
Much can be learned from reading the FDA’s public letters granting GRAS status to different stevia manufacturers. For one thing, all the big artificial sweetener brands (Splenda, Equal, etc) are now in the business of selling Reb A products. Hmmm.
The following is an excerpt from the FDA’s 2008 letter granting Purevia (Pepsi/Whole Earth) the use of Reb A in its products:
“Rebaudioside A is obtained from the leaves of S. rebaudiana (Bertoni) Bertoni by extraction with water, ethanol, or methanol and is concentrated with an adsorption resin to trap the desired steviol glycosides. The resin is washed with ethanol or methanol to release the glycosides. The elutant is de-colorized and de-salted by ion exchange and microfiltration to improve the purity of rebaudioside A. Recrystallization with alcohol (methanol or ethanol) and water mixtures results in a final product with a purity of greater than 95 percent. The residual ethanol or methanol is removed and the product is then spray-dried or granulated. Whole Earth provides specifications for rebaudioside A that include the content of rebaudioside A (≥95% by weight (w/w)) and limits for stevioside (<2% w/w), steviol (<0.005% w/w), moisture (<5%), lead (<1 mg/kg), arsenic (<1 mg/kg), cadmium (<1 mg/kg), residual methanol (<300 mg/kg), residual ethanol (<1g/kg), and microbial contaminants (within specified limits)."
Does that sound like pure natural stevia to you?
3. High Purity Stevia. Also sold as a sweetener but usually liquid or powder form for home-use. It is labeled as:
- High purity steviol glycoside extract
"High purity steviol glycoside extract" is basically equal parts Stevioside and Reb A.
Again, we can learn a lot from reading the FDA’s public letters granting GRAS status to Sweetleaf's high purity extract : (www.accessdata.fda.gov/scripts/fcn/gras_notices/grn000287.pdf )
“Typically, steviol glycosides are obtained by extracting leaves of Stevia rebaudiana Bertoni with hot water or alcohols (ethanol or methanol); the obtained extract is a dark particulate solution containing all the active principles plus leaf pigments, soluble polysaccharides, and other impurities. Some processes remove the “grease” from the leaves with solvents such as chloroform or hexane before extraction occurs. There are dozens of patents for the extraction of steviol glycosides. Kinghorn has categorized the extraction patents into those based on solvent, solvent plus a decolorizing agent, adsorption and column chromatography, ion exchange resin, and selective precipitation of individual glycosides. Methods using ultrafiltration, metallic ions, supercritical fluid
extraction with COz, and extract clarification with zeolite are found within the body of newer
Sweetleaf’s “process extracts the desired glycosides with membrane deionized water only, yielding a stevioside to Reb A ratio of about 50:50. The aqueous extract is purified to 60-65% using a membrane filtration system. Mechanical separation takes place at this juncture, and stevioside and Reb A are screened from large molecular weight and low molecular weight impurities. The resulting extract is finally polished with food grade ion exchange resin to achieve minimum glycoside specification. The polished extract is then concentrated to 30% Brix for spray drying. Following pasteurization at 85OC for 55 minutes, the pasteurized product is spray dried. An inlet temperature of 21OoC is utilized, and the outlet temperature is 95OC to reduce moisture to specification.” (The term “Brix” refers to the ratio of solids (stevia extract) to water.)
Most stevia is processed using solvents. According to these documents SweetLeaf only uses water, which is probably better for us.
What's in Stevia, Truvia and Purevia?
If you want natural stevia, this is it! After actual leaves and GREEN powder, whole leaf concentrate is the most whole form of stevia available. The whole leaf is boiled down. It is thick, brown, goopy, tastes leafy and slightly bitter.
SweetLeaf's Whole Leaf Stevia is a great choice. Unlike leaves or green ground powder, it dissolves easily in foods, but is not for everyone's palate. All unprocessed or low-processed stevia will have a bitter or slight aftertaste. There's just no way around it. Some people love it. Some people hate it.
SweetLeaf's Whole Leaf Stevia is sold as a dietary supplement and is labeled as "premium quality stevia leaves (stevia rebaudiana bertoni)".
Next is your typical powdered or liquid stevia sold as a dietary supplement in health food stores.
What started out as green is now white or clear. That takes a lot of processing, perhaps bleaching. Needless to say, much of the plant has been removed and the steviol glycosides package has often been picked through. There's no way of knowing how many components of the stevia leaf remain.
Many people feel the pre-FDA approved dietary supplement stevia products tasted better. Now, all the formulations seemed to have been messed with to keep up with the super sweet Reb-A product.
There's also the matter of fillers. Many use alcohol, maltodextrin, glycerin, etc. This NuNaturals stevia, sold as a dietary supplement is alcohol-free but uses glycerin as a filler.
I think Sweetleaf's Sweet Drops, made from High Purity Steviol Glycoside Extract, is the cleanest tasting form of stevia out there. As the above FDA letters show, SweetLeaf uses only water in its processing and in its fillers.
SweetLeaf labels this product as "Organic Stevia Leaf Extract”.
I love this product, but like any highly refined stevia, I use it with caution. Unlike crude forms of stevia, which have been around for years, these highly refined extracts have not, so I don't use it everyday like I did at first. I use it when it's most effective in recipes or for occasional bubbly drinks.
Pepsi co-owns Purevia. On their website Purevia states:
“Made from the pure, sweet, extract of the stevia plant, Reb A.” and “Reb A is extracted into its purest form through a series of natural processes, and then blended with natural flavors and other natural ingredients to create PureVia™ sweetener.”
Purevia’s ingredients as per their website: “The purified Reb A extract is then blended with isomaltulose (a natural sweetening agent also found in honey and sugar cane), erythritol, cellulose powder (which acts as a bulking agent) and natural flavors to give PureVia™ a clean sweet taste with the granular texture of sugar.”
Verdict: PureVia is hardly a stevia product at all. It is mostly made up of other sweetening agents like erythritol and isomaltulose. It uses the Reb-A stevia product which the FDA acknowledges is not stevia.
Truvia is owned by CocaCola and claims that their sweetener is “Sweetened with stevia”. Yet, Truvia’s ingredients listed in order of content are: Erythritol, rebiana A, natural flavor.
The word “natural” appears all over the packaging and the website claims that Erythritol “is actually a naturally fermented sugar alcohol that’s found in grapes and pears”.
While Erythritol does occur in natural fruit it’s so scant that it would be too expensive to be mass-extracted. Food grade erythritol is made by fermenting the natural sugar found in corn…and unless labeled as non-gmo…..this corn is usually genetically modified.
Truvia states: “we steep the leaves in a process like making tea.” Coca Cola’s 40 step patent is described here. I don’t know about you, but it doesn’t take me 40 steps to make tea.
Verdict: The truth about Truvia is that it’s anything but natural, from its fillers down to its use of Reb A, which again is not stevia.
With big manufacturers now involved, the competition is fierce, which means to keep up, most stevia products out there contain cheap, inferior stevia accompanied by all kinds of fillers.
I truly hope that veteran stevia companies like SweetLeaf will hold on to those values that existed before stevia became the new "it" sweetener. Truthfully, there's really no way for the average consumer to know what is in refined stevia. So use it sparingly, and every spring do as I do....plant yourself a stevia plant to pick and munch on whenever you walk past... just to remember the special taste and humble beginnings of the little stevia plant.
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