Stevia leaf extract and unblended xylitol offer the strongest potential for sweetening chewing gum, according to experts.
Cargill claims that stevia leaf extract offers the best prospect as it contains no calories and is widely perceived as natural among consumers.
Xylitol supplier and gum manufacturer Xylitol Canada on the other hand contends xylitol used alone is equally natural and can provide a like-for-like sugar replacement with dental health benefits it claims stevia does not possess.
Sweeteners in gum
Jan de Lobel, senior application specialist of sugar confectionery at Cargill, said: “Nowadays most chewing gums on the European market are already sugar free.”
“With mint gum people don’t focus on the sweet taste, it’s more about the freshness. However, it is a different approach with fruit gums.”
Many mint gums contain sweeteners, both in the gum base and in the coating, mainly for the bulking function and functional properties and not to provide sweetness.
If a high intensity sweetener is used then it is typically acesulfame-k, sucralose or aspartame, which are all artificial.
Stevia and gum
De Lobel said that stevia leaf extract carried the most appeal as an alternative high intensity sweetener.
“You get it from a natural source, it’s sugar free and it is not having any calories.”
He said that stevia leaf extract in gum took longer to kick in but then stayed longer in the mouth. Gum sweetened with stevia leaf extract also has the advantage of being free from producing a laxative effect unlike sorbitol.
De Lobel said that stevia leaf extract could be used to sweeten both the gum base and the gum coating, but was more commonly used in the gum base.
Out of the steviol glycosides, he said that Reb A and B gave the best sweetness in gum and were the only varieties approved in the EU.
Cargill’s stevia brand Truvia is being used in iGum’s FreeGum to provide sweetness for the product. Wrigley's Japanese unit also produces a stevia-based sugar-free gum. De Lobel said that some of Cargill’s competitor’s added enhancers in combination with stevia leaf extract to increase the sweetness, but Cargill uses only the stevia leaf extract.
For the bulking function, Cargill uses a combination of polyols; or sugar-free bulk sweeteners providing fewer calories; from its own portfolio such as sorbitol, maltitol syrup, mannitol and erythritol. “This gives you a certain texture and longer chew,” said de Lobel.
Xylitol in gum
“Stevia is a good option, but if you had a pure 100% sweetener, they add things to it to make it not so sweet,” said Julie Reid, vice president and director of sales of Xylitol Canada the leading xylitol supplier in North America.
“Xylitol is emerging into the market and it’s gaining a lot of awareness.” Actor Gwyneth Paltrow for example has included xylitol as an ingredient in recipes for her cookbook.
“It may not last as long (10-15 mins in gum), but it’s a functional gum that gets rid of the bad bacteria in your mouth,” said Reid.
Xylitol has been used as a sweetener in gum for some time, but has risen in prominence since the European Food Safety Authority (EFSA) approved a health claim from confectioner Leaf in 2009 to say that 100% xylitol sweetened gum reduces dental plaque.
Xylitol can be extracted from any woody fibrous plant material, typically corn cobs or trees. It works as a complete replacement for sugar in food products that serves both the sweetness and bulking functions without the need for other sweeteners.
Reid said that the majority of xylitol on the global market came from suppliers in China. She warned that safety and traceability were risks manufacturers took when sourcing xylitol from China, which typically extracts xylitol from corn cobs. Xylitol Canada uses xylitol from birch trees and poplar trees grown in North America.
Xylitol health claims
A product sweetened with 100% xylitol is able to make a sugar-free claim. Reid said that Xylitol ranked 7 on the glycaemic index, making it safe for diabetics. She added that xylitol contained 40% less calories than sugar and 75% less carbs.
In the EU, a chewing gum sweetened with 100% xylitol can carry a claim to say it reduces dental plaque. The effect is obtained when a consumer chews 2-3g of chewing gum sweetened with 100% xylitol at least 3 times per day after the meals. However, the European Food Safety Authority (EFSA) rejected the claim when xylitol was used in combination with other sweeteners. As an intense sweetener, xylitol can also claim in the EU to maintain tooth mineralization and reduce post-prandial glycaemic response.
Reid said that gum manufacturers often blend xylitol with aspartame to save on costs. “Xylitol is more expensive than other sweeteners grown in a lab,” she said.
Despite the increased cost from using 100% xylitol, Xylitol Canada’s own brand gum, Xyla, retails at $1.29 for a 12-piece blister pack. By comparison Wrigley’s popular 5Gum (sorbitol, mannitol, aspartame and acesulfame K) retails at around $1.49 for a 15 stick pack.
Although Xylitol Canada produces its own xylitol gum, Reid said that the company would welcome xylitol supply requests from large gum manufacturers.
Products using xylitol must carry an on-pack warning that the sweetener causes a laxative effect when consumed in excess. Reid said that xylitol’s laxative effective was less powerful than sorbitol or maltitol. She added that the effect was mainly experienced by first time users and claimed that the body adapted to the ingredient over time.