Mention a cola drink or peppermint candy and people may start salivating at the thought of the sweet taste. Yet the products may generate flavor issues, problems big enough to have formulators searching for flavor-masking alternatives.

Menthol may add a wanted cooling effect to confectionery items, especially mints and chewing gum, but it also may add unwanted bitterness.


“There is a great demand for more cooling in confectionery products, and increasing the menthol level yields a bitter taste,” said Deb Kennison, vice-president of applied flavor science and technology for Symrise, Teterboro, N.J. “Symrise has developed a blend of proprietary masking materials that, when used in precise combination, helps minimize the bitterness in high menthol and carboximide cooling systems.

“It is important to optimize the cooling systems together with complementary flavors and specific masking agents. It is very much a systems approach.”

The research and development center for Kraft Foods has applied for a patent that involves using vitamin E in the presence of at least one fat to mask the bitterness caused by menthol levels. Potential applications include panned chewy candies, chewing gum and chocolates.

Menthol has a cooling effect on the skin and mucous membranes of the mouth and is used as a flavoring agent in a range of products, according to the patent filing. Many confectionery products are mint-flavored and contain moderate to high levels of menthol. Peppermint oil generally contains about 45% to 55% menthol. Menthol’s disadvantages include a strong minty odor and harsh notes.

A vitamin E compound is effective on the overall taste profile of the bitter-tasting substance, particularly when administered in the presence of at least one fat. Tocopherols (vitamin E) are found in vegetable oils, nuts, seeds and whole grains. Naturally produced forms of tocopherol may be used as well as synthetic forms.

According to the patent filing, the taste-masking mixture may be incorporated as a center-filling within a confectionery item. It also may be mixed with other ingredients and/or distributed homogeneously throughout the confectionery item.

Senomyx, Inc., San Diego, has its own bitter-blocker program. One of its ingredients, the S6821, has demonstrated activity against bitter-tasting ingredients such as menthol as well as soy protein, whey protein, caffeine, cocoa and stevia extracts.

Senomyx, through its cooling taste program, seeks to identify novel cooling agents that have advantages over currently available agents such as menthol. Senomyx is in the early stages of developing a new cooling agent.

Firmenich, a privately-owned company based in Geneva and involved in the global flavor business, has exclusive commercialization rights for the new flavors developed under the Senomyx cooling taste program. Firmenich is evaluating additional cooling agents for potential future development.

The Smoothenol line of masking systems from Sensient Flavors, L.L.C. offers ingredients that have the ability to mask off-notes such as bitterness, astringency and metallic notes, said Jerry Keys, master flavorist at Sensient Flavors, Indianapolis.

“Advancement in menthol masking has been somewhat stagnant in recent years due to the industry focus on modern day sweeteners,” he said. “However, recent innovations in sweetener masking have motivated industry efforts to shift back to a focus on menthol masking.”

High-intensity sweeteners, especially when used in soft drinks, have other taste issues that may require flavor-masking ingredients.

“Masking high-intensity sweeteners has been a challenge over the years due to the shifting palate preference of consumers who initially had an adverse reaction to basic off-notes,” Mr. Keys said. “However, they have since become more accustomed to some of the common taste attributes of products with high-intensity sweeteners. As a better understanding is gained at the molecular level through sensory and consumer paneling, modifications have been made to improve flavor solutions systems.”

Many sweeteners have multiple problems, not just aftertaste, Ms. Kennison said.

“For example, stevia can have metallic and licorice off-notes, a delayed release, a lack of body/mouthfeel and a lingering aftertaste,” she said. “We’ve been able to bring the taste impression of these sweeteners much closer to sugar (the gold standard) on all these parameters.”

Some flavor-masking systems are designed specifically for stevia extracts. Wixon, Inc., St. Francis, Wis., offers Mag-nifique for Stevia, a technology-based ingredient that reduces the bitter aftertaste caused by stevia while enhancing the stevia in the application.

Sweeteners themselves may act as flavor-masking agents in whole grain products. Auntie Anne’s Pretzels, a 1,325-unit chain, in January introduced a honey whole grain pretzel with one daily serving of whole grains.

“Many bakers are turning to honey to capitalize on the ingredient’s popularity and ability to mask the off-flavors of whole grain and whole wheat products,” said Catherine Barry, director of marketing for the National Honey Board, Firestone, Colo.

Masking bitter off-notes in whole grain products may be complex because it may involve a variety of factors, Mr. Keys said.

“Often several grains are present in a particular matrix due to the desire to achieve whole grain claims and health benefits,” he said. “Complex matrixes can prove difficult from a masking perspective in terms of understanding singular and multi-dimensional off-notes which require masking.”

Ms. Kennison said Symrise takes a threefold approach in masking off-notes in whole grain products: adding lubricity via saliva-stimulating agents, mouthfeel enhancers and fat simulators; masking the bitter and oxidized notes often present in whole grain products, particularly by enhancing sweetness; and using delivery systems to keep flavor from “complexing” in the systems.

“Often the overall flavor/masking delivery is diminished due to fiber absorbing the flavor,” she said. “Finding a system that masks, but also frees up flavor and masker availability in these systems can eliminate some of the off-taste, even in heavily fortified and high fiber whole grain products.”

Better understanding of taste receptors on the human tongue may lead to further innovations in flavor-masking systems.

“One of the more significant challenges with masking in general is masking undesired notes while maintaining the desired notes,” Mr. Keys said. “Future advancements require an understanding on a molecular level of the negative attributes that are perceived by the taste receptors. Thereafter, experimental developments are filtered through advanced technical and sensory evaluations to understand which systems show positive benefits.”