The stevia leaf (Stevia rebaudiana) has yielded exciting, zero-calorie natural sweeteners for food and beverage formulators over the past decade. Now, the leaf is offering formulators another exciting, healthy ingredient: antioxidants. Stevia supplier PureCircle (Chicago) announced that it is ready to roll out what it says is the first “commercially viable” antioxidant ingredient from the stevia leaf. The firm made the announcement at last week’s Institute of Food Technologists (IFT) Annual Meeting and Food Expo in Las Vegas.
The company says that while researchers have known that stevia leaves contain antioxidant properties, PureCircle claims it is the first company to be able to extract these antioxidants on a global scale from the stevia leaf thanks to a unique extraction and purification process.
The primary antioxidant compounds in the stevia leaf are chlorogenic acids, said Carolyn Clark, director, global marketing and innovation, PureCircle, at the IFT show. Chlorogenic acid, she said, is also a well-known antioxidant in green coffee bean extract. In fact, she said, the chlorogenic acid in Stevia rebaudiana exists at about 1.5% dry weight in the leaf. “By comparison, Reb A, the most commonly known steviol glycoside, is about six times that. So while the quantity is much smaller than Reb A, there’s enough where it still makes sense for us to go ahead and extract it,” Clark said. This also means PureCircle is able to utilize more of the stevia leaf which otherwise may have been discarded as waste.
In terms of power as an antioxidant, Clark said, the chlorogenic acids from stevia have an ORAC (Oxygen Radical Absorbance Capacity) level of about 9000 μ mol TE/100g—higher than the ORAC values of, for instance, coffee bean extract (2500 μ mol TE/100g), blueberries (9621 μ mol TE/100g), cranberries (9090 μ mol TE/100g), and green tea (1253 μ mol TE/100g). (Values are per the USDA’s database Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods, Release 2 (2010), which has since been discontinued.)
Clark said that PureCircle hopes to get GRAS approval in 2018 to clear the path for the antioxidant’s use in food and beverages. She said that it can already be used in dietary supplements without requiring a new dietary ingredient (NDI) notification because “it falls under the stevia leaf extract use that’s already out there today in the supplements space in the U.S.”
Meanwhile, she said, the company will also be working to build up its commercial-scale production of the ingredient. PureCircle would sell the antioxidant as a standalone ingredient alongside its other stevia sweetener offerings. She said the stevia antioxidant’s taste is “mild” and “clean” because of its plant base. “Some kinds of plant-based antioxidants that are trying to do similar things often have an off-note, so we’re excited to work with formulators” with this ingredient, she said. Already, the company is sampling the ingredient with some customers.
Also at IFT, PureCircle highlighted its newly announced proprietary StarLeaf Stevia rebaudiana leaf that the company developed through its PureCircle Stevia Agronomy Program. According to PureCircle, the company cross-bred the StarLeaf leaf to contain more than 20 times more sugar-like steviol glycoside content compared to standard stevia leaf varieties, particularly the glycosides Reb M and Reb D. Clark said that this is the first brand-name leaf to come out of the PureCircle Stevia Agronomy Program. Through StarLeaf, Clark said, PureCircle will be able “to create more of those sugarlike” stevia extracts.