HFCS is near the top of the list of controversial ingredients from which health-savvy consumers are moving away. Options for manufacturers include organic sugar and evaporated cane juice, rice syrup, other grain-based sweeteners, tapioca syrup and honey. But as 2010 approaches, the future for the category may exist beyond the identification of new sweeteners. Mark J Tallon, PhD, gives a science-based roundup of the field

Sweeteners are always on the mind of the food technologist as the need for functional foods and beverages that taste great remain in high demand. According to market research firm Freedonia Group, the global sweetener market was worth $12 billion in 2008. The natural and alternatives market to high-fructose corn syrup (HFCS) is expected to account for about 12 per cent of the total sweetener market by 2013.

The success and growth of alternative and natural sweeteners is due to their ability to address many consumers' concerns about sugar, HFCS and artificial sweeteners. These concerns revolve around issues of safety, and particularly HFCS's relationship to autism, obesity and cancer. In fact, in addition to conferring a message of health, natural sweeteners tend to also be low- or unprocessed, low calorie, low on the glycaemic index (GI), and mindful of sustainable and environmental concerns.

Stevia makes all the right moves
Stevia rebaudiana Bertoni is a member of the chrysanthemum family. It was discovered by natives of Paraguay who used extracts of its leaves to sweeten the bitter drink called maté. In 1931, French researchers then isolated the sweet components from the stevia leaf known as steviol glycosides, of which stevioside and rebaudioside A (Reb-A) are the most abundant. In December 2008, the FDA granted the use of Cargill's Reb-A extract generally recognized as safe status for use as a general-purpose sweetener. Since then the US market has been chasing the heights stevia achieved in countries such as Japan, where it accounts for more than 40 per cent of the total sweetener market.

On top of stevia's movement into multiple products based purely on a taste platform, this sweetener is becoming increasingly accepted as innately 'nutritive,' offering multiple health benefits. In 2009, DSM moved to exploit the health benefits stevia may afford by applying for a patent linking stevia to improved brain function and cognitive health. The patent (WO 2009/071277) focuses on the use of stevia and its constituents, such as steviol and stevioside, which are suggested to perform three health and performance functions:

According to the patent, there are a selection of in vitro and animal studies identifying the mechanism behind stevia's effects on cognitive function, and also specific trials demonstrating learning and memory benefits. The doses used in these studies were equivalent to 3.5g-31.5g per day, suggesting the physiological health benefits of stevia are only possible at doses not likely achievable when using stevia only as a sweetener.

With other companies looking to utilise differing components of stevia and ratios of its extract, I would expect to see peer-review publications beginning in 2010 identifying its specific health benefits.

Sweetness enhancers vs bitterness blockers
Like other sweeteners, Reb-A poses some significant challenges for the food technologist. Reb-A has a taste profile many find difficult to endure in its natural form due to its inherent bitterness and mouthfeel. When such taste challenges are encountered, the first thoughts are to mix in other sweeteners or to utilise sweetness enhancers. However, companies are beginning to pay more attention to other taste receptor-based technologies to overcome issues currently faced by products such as Reb-A.

Bitterness blockers have become the talk of the flavour market in recent months, and since the 2004 FDA approval of Linguagen's AMP bitter blocker ingredient, other companies have been looking to develop this technology further. According to a second-quarter report from Senomyx, progress in its 'Bitter Blockers Program' during taste tests demonstrated that the company's bitter blockers (s0812) provide statistically significant reductions in the bitterness of a variety of product prototypes and food ingredients including tea, cocoa, menthol, Reb-A, and the widely used sweeteners Ace-K and saccharine.

Senomyx is working on commercial applications of such technology with the likes of Solae where bitter blockers may modulate bitterness in certain soy-based products. Optimising bitter blockers and additional taste tests are ongoing. Although these are early applications and bitter blockers are in the early stages of development, the growth of sweeteners such as Reb-A ought to aid in their commercial success.

Next-generation sweeteners
Sweetener enhancers, bitterness blockers and approved sweeteners are well into commercial development. As with most functional ingredients, the nation to innovate first is Japan. In April 2009, Ajinomoto's food group submitted to the FDA a dossier for authorising the marketing of a new sweetener from the same amino acids as aspartame.

This new sweetener is a derivative of the aspartame dipeptide composed of L-aspartic acid and L-phenylalanine in the form of methyl ester. Although similar to aspartame with a sweetening power approximately 200 times higher than that of sucrose, this new sweetener has a taste closer to sucrose. Because of this it is more intense in its sweetness than aspartame, meaning less can be used in formulations (especially beverages). In addition, Ajinomoto claims it is stable to heat treatment, which also makes its use more flexible than aspartame.

At present a decision from the FDA on this new sweetener is expected within two years, with similar applications prepared for the European agency EFSA.

Market researcher Freedonia suggests that intense sweeteners will retain the largest share of the food and soft-drinks market through 2010.

There are many sweetener alternatives on the market, from exotics such as luo han guo to the more traditional honey. However, the future for the sweetener category is beginning to extend beyond the identification of new sweeteners to the optimisation of sweetness through novel enhancers and bitterness blockers. The category will continue to grow in line with calorie-free foods and beverages, with the biggest area for evolution revolving around the research on the specific health effects possible from the current crop of natural sweetener alternatives.

Mark J Tallon, PhD, is chief science officer of NutriSciences, a London-based consultancy firm specialising in health-claim substantiation, product development and technical writing. www.NutriSciences.net

Disclaimer: The author does not work for, and has not received remuneration for the mention of, any of the companies or associated products within this article.

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