It has been almost a quarter of a century since the high-potency sweetener aspartame received broad approvals for use in foods and beverages, a regulatory action that stimulated a major revolution in food and drink formulation practices. Until that time, and since the 1969 ban imposed by the FDA on the use of cyclamate, saccharin was the only high-potency sweetener approved for use in the United States, and the ?diet products? sector was small.
Approval of aspartame provided major stimulus to the development of diet beverages, in particular, since it had now become possible to deliver substantially higher-quality drinks with much less sensory compromise from their full-sugar equivalents.1 A second consequence of the success of aspartame was that other companies were stimulated to pursue their own sweetener discovery and development programs, with the result that acesulfame-K, sucralose and the more recently approved neotame now compete with aspartame in this market. Alitame, originally discovered by Pfizer and now owned by Danisco Sweeteners, is still waiting in the wings.
Diet beverage markets grew steadily throughout the 1980s and 1990s, but growth in that sector then levelled off until the recent impetus provided by obesity concerns and the potential contributory role of carbohydrate sweeteners, particularly fructose.2
Now, diet beverage markets are on the move again, and there is also much development activity within the major beverage producers to formulate sugar-reduced versions of their products, sparking a renewed interest in high-potency sweetners. Such sweeteners either deliver no energy or are used at such low concentrations that even those that do provide energy are virtually calorie-free. They are essentially mono-functional ingredients.
Naturally, they are most suited for use in products that can easily accommodate additional water to make up the bulk that is inevitably lost through the removal of sucrose or high-fructose syrups. This explains why beverage applications account for the major share of the market for these types of ingredients, and why there is only a minimal market penetration of sweeteners into sectors such as baking.
It is important to acknowledge that high-potency sweeteners provide no intrinsic benefits to foods or beverages. The rationale for using them in product formulations is straightforward: Their use leads to reductions in both the caloric density and sugar content of products.
Many experimental studies supporting the beneficial role of high-potency sweeteners in weight-control programmes have been published. For example, in a study involving feeding a restricted diet sweetened with aspartame to obese subjects, Blackburn showed significant effects on body weight that were apparent for as long as two years after the study began.3 An additional study involving an unrestricted diet consumed by overweight subjects saw significant improvements in a number of key indicators such as body weight, fat mass, body mass index and blood pressure for the group consuming high-potency sweeteners compared to the group consuming sugar.4
In addition to saccharin, four high-potency sweeteners have received FDA regulatory approval. They are aspartame, acesulfame-K, sucralose and neotame.
Aspartame remains the standard against which other high-potency sweeteners are compared. Although there are limitations with respect to stability and solubility, industry has developed formulations and manufacturing procedures that accommodate it without undue difficulty. It delivers an excellent quality of taste in most product matrices and generates remarkable levels of ?free? sweetness because of its high levels of sweetness synergy in blends with acesulfame-K, also known as ace-K.
In addition to the quantitative synergy in blends with ace-K, such blends can often deliver an improved taste profile due to the rapid sweetness onset of ace-K and its ability to cut through aftertaste characteristics. It is for these reasons that aspartame/ace-K blends are often selected. Ace-K is not a stand-alone sweetener. Its bitter aftertaste at high concentrations ensures that it is always used in blends where it constitutes the minor component.
Sucralose is a more recent addition, having received FDA approval in 1998. Since then, market development has been steady.
Sucralose delivers a good, stable source of sweetness, although its sweetness may linger longer than might be optimum. As a consequence, it is often blended with other sweeteners to improve its temporal profile. It is a particularly attractive candidate for use in sugar-reduced products because it renders them stable, with no shelf-life concerns.
Neotame is the latest high-potency sweetener to have received FDA clearance. A derivative of aspartame, the structural changes carried out in preparing neotame raise the sweetness of aspartame approximately 40-fold. At this level of potency, neotame, not surprisingly, delivers a sweetness that does linger in the aftertaste and so it is likely it will most often be blended with other sweeteners. Its market prospects are positive.
Stevioside is not an FDA-approved sweetener, so its use as a ?supplement? and in supplements will always constrain its market. In addition to these regulatory barriers, stevioside does not deliver a clean sweet taste, as its sweetness is accompanied by a bitter/licorice aftertaste.
Alitame, in contrast, which remains under regulatory review by FDA, does deliver a high-quality sweet taste. However, it has the potential to interact with some important food and drink components such as caramel and ascorbic acid to release a sulphur odour; unless this can be overcome, its market potential will also be constrained.
The high-potency sweetener market has exhibited great dynamism in recent years and shows every indication of continuing to do so. New nutritional drivers are now opening up yet more, and potentially significant, market opportunities. With these high-potency sweeteners, the tools are available for the industry to respond to those market opportunities.
Michael G Lindley, PhD, is director of LinTech, a technical consultancy specialising in supporting the development of new functional foods ingredients and the foods and beverages in which they are formulated. He has 30 years of experience providing scientific and technical support to food companies worldwide.
All correspondence will be forwarded to the author.
1. Aspartame: Commissioner?s final decision. Federal Register 1981; 46:38284-308.
2. Teff KL, et al. Dietary fructose reduces circulating insulin and leptin, attenuates postprandial suppression of ghrelin and increases triglycerides in women. J Clin Endocrinol Metabol 2004; 89:2963-72.
3. Blackburn GL, et al. The effect of aspartame as part of a multi-disciplinary weight-control program on short-term and long-term control of body weight. Amer J Clin Nutr 1997; 65:409-18.
4. Raben A, et al. Sucrose compared with artificial sweeteners: different effects on ad libitum food intake and body weight after 10 weeks of supplementation. Amer J Clin Nutr 2002; 76:721-9.