The recent decision to remove stevia extracts from most vitaminwater varieties shows the need for continued research on the high-intensity sweeteners. The race to reach the highest level of Rebaudioside A, a sweeter part of the stevia leaf, has slowed. Suppliers of stevia-based sweeteners in 2014 are taking other innovative paths. A strategy to solve taste issues features a customized approach to using several steviol glycosides, not just Reb A. Another approach does not use the leaf. Instead it involves fermentation of yeast to create more economical stevia-based sweeteners.

The experiment of using stevia in vitaminwater, a brand owned by the Coca-Cola Co., lasted less than a year. After consumers complained about the taste, the decision to remove stevia as a sweetener appeared on the vitaminwater Facebook page: “We tinkered with the taste of vitaminwater, and our fans haven’t had the greatest things to say about it. So we’re changing back to the taste you know and love.”

Yet surveys give credence to stevia’s future as a sweetener. Tate & Lyle, P.L.C., London, cited data from Innova Market Insights showing 2,860 new products launched globally in 2013 incorporated stevia, which was up 56% from 2012. To compare stevia with other high-intensity sweeteners, 6,373 new products with sucralose were launched and 3,633 new products with aspartame were launched.

Along with Splenda sucralose, Tate & Lyle now offers a Tasteva stevia sweetener. This June at the Institute of Food Technologists’ annual meeting and exposition in New Orleans, Tate & Lyle unveiled a survey found 63% of people preferred a fruit drink sweetened with Tasteva over another fruit drink sweetened with Reb A. The fruit drink with Tasteva had a “pleasant aftertaste” or “no aftertaste,” according to 63% of the people. The fruit drink with Reb A had an “unpleasant” aftertaste, according to 54% of the people.

“This research is important because it shows manufacturers they can bring those on-trend, better-for-you products to market without sacrificing clean, sweet taste,” said Amy Lauer, marketing manager, North America for Tate & Lyle.

Tate & Lyle at the I.F.T. event sampled a blood orange sangria “mocktail” sweetened with stevia that had 12 grams of sugar and 60 calories in an 8-oz serving, which compared to a blood orange sangria “mocktail” sweetened only with sugar that had 26 grams of sugar and 220 calories in an 8-oz serving.

Studying steviol glycosides

PureCircle has a Stevia 3.0 program in which researchers study different steviol glycosides. Each glycoside has a different taste profile, said Faith Son, vice-president of global marketing and innovation for PureCircle, which has a U.S. office in Oak Brook, Ill. Through exploring the glycosides’ traits and ways to combine them, PureCircle has created more than 20 ingredients. Last year PureCircle received a letter of no objection from the Food and Drug Administration for the Generally Recognized As Safe (GRAS) status of Reb D as a general purpose sweetener for foods and beverages.

Cargill, Minneapolis, launched its ViaTech line of stevia-based sweeteners in March of this year. Cargill’s proprietary taste prediction model finds customized ways to work with different steviol glycosides. Companies, when using ViaTech, will not need a bitter-blocker or other flavor modifier to achieve 50% calorie reduction in some applications, said Scott Fabro, Cargill’s global business director for high-intensity sweeteners.

“Cargill has found a way to optimize the steviol glycosides in ViaTech products,” he said.

Cargill identifies the profile, such as the sweetness level, of each specific glycoside, he said. When combining steviol glycosides, Cargill researchers found the sweetness level in certain ratios may not be a case of one plus one equals two. It may be a case of one plus one equals 1.5. The expected sweetness level in the combination of steviol glycosides may not be reached while bitterness increases.

Fermentation to save costs

Low percentages of the amount of specific steviol glycosides in stevia leaves may hinder efforts to make the sweeteners more economical. This cost issue has led DSM, Delft, The Netherlands, to work with fermentation of yeast, not leaves. DSM in June said it was on its way to building a high-intensity sweetener platform based on fermentation.

“We are confident of DSM’s ability to provide stevia extract at a competitive offer with the promise of quality, sustainability, safety and reliability coming directly from our facilities,” said Hans Christian Ambjerg, president of DSM Food Specialties.

Steviol glycosides may be produced through fermentation anywhere in the world, according to DSM. The process uses fewer raw materials, requires less arable land and consumes less water, according to the company.

DSM has filed a number of patent applications relating to the fermentation-based production of steviol glycosides, said Greg Kesel, regional president Americas for DSM Food Specialties.

“As a next step, we will be piloting our technology in 2014 by making food-grade samples available to our customers,” he said.

Cargill and Evolva Holding SA, Reinach, Switzerland, are in a joint development program for fermentation-based minor steviol glycosides. This year the program achieved a technical milestone that will result in Cargill making a $1 million milestone payment to Evolva.