The science of food and flavors has come a long way when it comes to helping maintain quality and taste without sacrificing safety. Modifying flavors, whether enhancing them without changing them or masking bitter or off notes from necessary ingredients, requires an in-depth understanding of ingredients and their components. This can include everything from how products and their ingredients are processed, stored, and consumed to their fundamental chemistry.

From the moment a food is harvested or produced, it begins declining in taste, texture, nutrition, and safety. Also, sometimes the ingredients that work the best for a desired nutrition profile might come at a cost related to flavor. An oft-cited example is that of protein from legumes. Some are reported to leave a bitter aftertaste and some have what consumers call a “beany” taste — not so enjoyable in, say, a confection or sweet beverage.

Other formulations might need an extra flavor boost to better define a more delicate flavor note in a finished formula. Whether to impart the rich, comforting flavor of a roasted chicken soup or a beefy flavor in a meat analog, or to heighten a delicate raspberry flavor in a frozen dessert or a distinct note of a less common tropical fruit in a beverage, the need for flavor enhancement can be unavoidable. All of these challenges call for flavor masking, blocking, or boosting.

“Masking” and “blocking” are not interchangeable terms; they connote different—and often opposite—ways of covering up off notes in a food or beverage application. The ultimate role of masking flavors is to reduce off notes and give the food a neutral flavor profile. The approach comprises utilizing FEMA-GRAS (Generally Recognized as Safe, as determined by the Flavor Extract Manufacturers Association Expert Panel) flavor materials to create desirable taste (and/or aroma) attributes and reducing undesirable off notes.

Masking can involve using sweeteners, acids, salts, and flavor ingredients at a sub-threshold level so that the final taste profile stays neutral. Blocking, in contrast, involves changing taste attributes by means of a chemical process. 

Ingredients act as blockers by binding with, for example, the bitter taste receptor on the tongue, or by binding with the “offending” tastant compounds. They literally block the off note of a flavor from being perceived by the tongue.

It is thus important to identify chemical reactions that might occur and determine how quickly they will happen. It is also important for formulators and manufacturers to accept that some flavor reactions are not reversible — that is, flavor ingredients tend to deteriorate with time, and the freshest ingredients or ingredient systems should be used each time for stability in the finished product.

There is no universal “silver bullet” that acts as a blocking ingredient or process. The art lies in complementing the off note or distracting the taste buds by bringing the offending aroma or flavor to below the threshold level, thus bypassing perception during consumption.

 

INTERACTION CHEMISTRY

A key problem in blocking negative or unwanted flavor notes such as bitterness is uncertainty about ingredient interactions. This is because foods and beverages are tricky, complex matrices that obfuscate, modify, or change the behavior of individual components, and in the process, introduce unexpected off tastes.

THE ART IN BLOCKING OR MASKING LIES IN "DISTRACTING" THE TASTE BUDS BY BRINGING THE UNDESIRED AROMA OR FLAVOR TO BELOW THE THRESHOLD LEVEL.

“Bitter taste presents a barrier to overcoming global public health challenges,” says Erik Schwiebert, PhD, CEO and chief scientific officer of Discovery BioMed, Inc. The bioengineering firm is collaborating with taste and smell research labs at the Monell Chemical Senses Center to develop next-generation, high-throughput screening technologies using cloned immortalized bitter taste cells. The goal is to be able to rapidly identify bitter taste blockers so as to improve the taste and acceptability of nutritious plant-based foods.

Some traditional flavor enhancers and bitter blockers come from natural fermentation products. Food protein hydrolysates created by natural fermentation have been used for centuries by various cultures to boost flavor. Active fractions, consisting primarily of free amino acids and glutamate-enriched oligopeptides in fermented condiments such as soy sauce, partially modulate human sensory and bitter-taste receptor-expressing cells. This allows them to elicit a distinct umami taste in a product. 

These compounds also can reduce human-perceived bitterness and effectively suppress the intracellular ionic calcium response in the human bitter-taste receptor-expressing cells. In this manner, they help to improve flavor of foods made with bitter ingredients (like amino acids), along with bitter active ingredients such as saccharin, acesulfame K, and caffeine.

Sometimes, depending on the product, the simplest ingredients can be used to mask off notes. For example, in sweet formulations, two simple yet highly effective ingredients—sugar and vanilla—accomplish the task with a clean label and high consumer acceptance. Vanilla has a long history of enhancing sweet, spicy, and floral flavors. It is an integral ingredient in chocolate confections, complementing the cocoa while masking some of the bitterness from dark chocolate.

Trending ethnic flavors, such as the chili pepper condiment gochujang and fermented cabbage with hot pepper known as kimchi, originally were not as sweet as they are in Western food culture today. Bitter and pungent back notes from the peppers traditionally were counteracted with salt. Sugar is a recent addition to these dishes, and it is used primarily to make the products more suitable to the Western palate.

Developers have used sugar frequently to subtly counter undesirable flavor traits in savory formulations as well. And more recently, vanilla has been gaining greater attention for the same ability. It’s not uncommon for savory sauces and condiments to include vanilla to “even out” flavors and bring about subtle changes.

 

MEATY BOOST

The Abbot’s Butcher, Inc., a manufacturer of vegan analog versions of meat and poultry products, including herb-roasted chicken deli slices, beef and turkey burgers, Italian meatballs, Spanish chorizo, and ground chicken and beef, uses beets, tomatoes, and porcini mushrooms for their flavor-enhancing properties. 

These clean label meat analogs rely on key aroma compounds in raw and dry porcini mushrooms to create and enhance unique meat-like umami flavor and aroma. Raw porcini contains the chemical compound 1-octen-3-one. This gives the Abbot’s Butcher products an earthy aroma and flavor that is associated with roasted meats.

Dried porcini mushrooms contain 3-methylthio-propanal (also known as methional), which is a natural component in cooked potato-based snacks, such as potato chips, and comes from the breakdown of the amino acid methionine. Methional, in concert with 1-octen-3-one and pyrazines—other key aromatic compounds in dry porcini—create the flavors of roasted, toasted, or thermally processed foods in plant-based foods.

Natural, clean-label ingredients such as yeast extract, shiitake extract, tomato purée and extract, soy sauce, and soybean paste are commonly used umami-boosters in savory foods. They contain glutamic acid (glutamate) and 5’-ribonucleotides which act synergistically to elicit and enhance umami taste. Green Park Snacks, Inc., uses natural sources of glutamate and ribonucleotides to get a pronounced umami flavor in its Hippeas brand of flavored organic chickpea snacks. The ingredients are used in crafting the company’s Far Out Fajita, Sriracha Sunshine, Vegan White Cheddar, Pepper Power, and Bohemian Barbecue flavors.

Other savory snack companies horizontally expanding their portfolios through multiple flavor offerings also are taking advantage of enhancers to help create these subtle — and sometimes not-so-subtle — variations.

The Good Bean, LLC, an organic fava bean and chickpea snack company, uses tomato-derived ingredients to enhance the flavor of its snacks. So does Three Farmers Foods, Inc., makers of Pea Pops crispy chickpea snacks and Crunchy Little Lentil lentil snacks in such flavors as in Sriracha Slap, Wild Ranch, and Dill Pickle Pow. They rely on tomato powders, yeast extract, onion powder, and other natural ingredients to create their array of flavors.

 

FAMILIARITY BREEDS FLAVOR

Flavor is the familiar and comfortable element in alternative proteins—more specifically, plant proteins used in meat and dairy analogs—which constitute an influential and burgeoning category in foods and beverages.

Consumers continue to yearn for the taste that comes only from familiar methods of preparation such as roasting, grilling, and broiling. Chemistry is helping to develop an array of reaction flavors that provide unique and new savory characteristics to prepared foods and add to the ever-expanding feast of vegetarian meat substitutes.

The vegetarian meat analog market is growing at a rate approximately 50% faster than other packaged foods (according to a 2018 survey by consumer research group Nielsen Holdings, Inc.). This movement also is feeding into traditional markets and specialized markets that adhere to kosher, halal, and other dietary rules that are similar in prohibiting the consumption of meat or products derived from certain animals, such as pork, and prescribing the slaughtering of acceptable animals in a specific manner.

This paradigm shift came about due to a change in what consumers were willing to accept in products attempting to replace meat and poultry flavors. Powdered garlic and onion were poor substitutes for umami for those consumers trying to reduce or remove much-loved meat from their diets. So, too, have ingredient technologists found themselves struggling to recreate flavors in dairy alternatives, such as plant-based milk, yogurt, and ice cream that consumers would actually desire and crave.

While the plant-based category of foods was driven by a fundamental shift in consumer attitudes and behavior toward animal-derived products, what has created the thriving and growing success in the category is a flood of recent ingredient technological advances that have allowed formulators to successfully recreate non-vegetarian flavors and textures in vegetarian foods.

Reaction flavors play an important role in formulation with plant-based proteins. Plant-based foods, regardless of how they are prepared and preserved, lose flavor upon standing. Moreover, they require heating for palatability. Reaction flavors based on Maillard browning offer an elegant solution by mimicking the reactants of a traditionally cooked food that often includes fats, salts, glutamates, and/or other (non-reactive) proteins, as well as processing aids, to give a fully rounded savory flavor.

These reaction flavor mixtures can, in a flash during reheating, release the complex Maillard browned, roasted, and savory flavors as if the plant-based analog or sous vide food had been subjected to a full day of roasting, baking, or stewing.

Savory reaction flavors can deliver tastes otherwise not available in a wholly vegan product that can meet kosher requirements and also support Hindu, Jain, and Buddhist cultures that adhere to strict vegetarian practices. Reaction flavors offer a complex cascade of savory flavors and flavor solutions that cannot be duplicated by any other flavor blends.

Reaction flavors can help enhance and preserve the taste of meaty and savory foods and can add layers of processing notes that develop and change while being cooked, all without involving any animal-derived ingredients. This is a boon for the meat substitute category which, according to research group Packaged Facts, is predicted to reach almost $6.5B by 2023.

 

DAIRY SHIFT

The trend away from animal-based milk products toward plant-based analogs of milk, creamers, yogurt and ice cream has been flourishing. Practically all major food brands have at least one alternative-protein brand in their dossier. This growing preference for dairy analogs made from nuts, grains (such as oats, barley, and rice), seeds, and legumes shows little sign of slowing down.

Research group Mintel reports booming growth in the dairy alternative market, with US household penetration growing from more than 27% in 2013 to 55% in 2016. Mintel estimates annual sales of plant-based nondairy beverages at $2B and forecasts the category’s growth to $3B by 2020. Innova Market Insights estimates the global market for dairy-alternative drinks was nearly $16.5B in 2018.

Califia Farms, LP, makes a line of certified organic dairy alternative beverages with organic nuts, water, oat fiber, and sea salt. The company makes its milk alternatives from non-GMO almonds, cashews, and coconuts, without soy, carrageenan, or gluten, and processes the ingredients differently than other nut-milk manufacturers for a more pronounced nutty flavor and an enhanced texture profile.

Recently added to manufacturers’ toolboxes, almond protein is an ingredient that checks off all the boxes for consumers and processors alike when it comes to working with plant-based protein. Almond protein has a pleasant, nutty flavor and helps to mask the bitter notes of other plant-based proteins, such as those derived from legumes like soy and pea.

Sea salt plays a prominent role in supporting the nutty flavor in Califia Farms’ milks. The company’s Full Shot Cold Brew Coffee incorporates MCTs (medium-chain triglycerides) in the base matrix to help accentuate the flavor of cold-brewed coffee in the product, while the cold-brew process itself provides superior taste due to maintaining a higher concentration of antioxidants and lower acidity (up to 70% less) than hot-brewed coffee. A slight amount of sea salt further smoothes and rounds out the coffee flavor.

 

BETTER BEVERAGES

Flavor deterioration during storage challenges beverage manufacturers. The stability of aroma compounds in beverages, whether the flavor is intrinsic to the primary ingredients or has been added as a flavoring component, is considerably greater in low-oxygen, oil-based matrices than in aqueous systems. The addition of coconut-derived MCTs offers substantially greater stability to the volatile compounds of coffee and nuts than do the more traditional additions of sunflower oil or soybean oil.

Formulated flavor mixtures tend to undergo significant chemical reactions during storage due to oxidation and acetal formation. Acetal formation is an acid-catalyzed equilibrium phenomenon that can be prevented with inert ingredients that act as natural solvents. MCTs can serve that function and deter the sensitivity of reactive carbonyl compounds found in vanillin, citral and benzaldehyde.

The taste and aroma of water is critical to how consumers perceive the bottled product and its value. A 2018 national survey by Toluna, Inc., reported that more than half of Americans tend to “focus more on healthy lifestyle choices in warmer months,” and almost two-thirds (61%) say they “try to drink more water to lose weight and become healthier.” Drinking water, however, is difficult for 39% of Americans because the “lack of flavor” is a turnoff.

As the recent flood of flavored, zero-calorie waters attests, modern flavor chemists and researchers have been successfully transforming the aesthetics of drinking water and changing how people choose water. They’ve done so by identifying and combining olfactory substances already prevalent in the food supply rather than creating new flavorings.

The result has been an almost cult-like following for flavored waters. Cantaloupe, cucumber, and watermelon extracts act as flavor enhancers for National Beverage Corp.’s LaCroix carbonated water beverages. In addition to the more pedestrian lime, cranberry, orange, etc., flavor combinations such as Melón Pomelo (cantaloupe and pink grapefruit), Kiwi Sandía (kiwi fruit and watermelon) and Muré Pepino (blackberry and cucumber) have proven to be big hits with consumers.

Not only flavor trends but paradigm shifts in consumer preferences and demands, such as the explosion of plant-based eating, act as a bellwether of the importance of flavor enhancers and boosters. The health and wellness lifestyle drive, and its shift away from animal-based protein sources to plant-based options, is just one example of the types of dramatic developments happening across markets that result in new ingredient technology. Using the “flavor first” approach as a key to success, manufacturers seeking to develop foods and beverages that can present new opportunities and challenges can rely on flavor houses to help them enhance and boost the flavors of their products in development without compromising on the final result.

 

Are You Nuts? Here’s Another Approach to Flavor Masking

By Bob Garrison

Nashai Biotech Vice President of Business Development Barrett Jacques

Nashai Biotech Vice President of Business Development Barrett Jacques meets industry trade editors to talk about new MinusCal protein and weight management bars. Two varieties utilize almond butter, in part as a masking agent for green tea extract.

This February saw the Almond Board of California host a February tour of Nashville, Tenn., for industry trade editors. That event included a meet-and-greet presentation with Barrett Jacques, director of business development for Nashai Biotech LLC, a functional ingredients company and parent to the new MinusCal bars line.  

MinusCal bars feature Nashai’s patented Choleve, a proprietary blend of fermented tea extract, that is said to work by blocking the absorption of fat in the small intestine. Three new 1.8oz bar varieties are: Peanut Butter (with chocolate chips), with 10g protein, 11g fiber and 4g sugar; Apple Cinnamon with 9g protein, 11g fiber, 6g sugar; and Chocolate (with chocolate chips), with 9g protein, 12g fiber and 4g sugar.

A study published in the Journal of the American Medical Association in 2003 demonstrated the effectiveness of the active compounds in Choleve in reducing LDL cholesterol. While researchers found it to be effective in doing so, an additional benefit noted in the study participants was weight loss.  

“We’re excited to have found a natural way to help people see the results they want, faster, while also providing them with a powerful tool for fighting hunger and fueling their bodies purposefully,” says Jacques. 

Jacques further described how MinusCal’s bar manufacturer recommended almond butter as a base for the brand’s Chocolate and Apple Cinnamon varieties. “Not only does almond butter provide a nice base for producing the uncooked bar, but it also serves as a tasty masker to Choleve’s slightly bitter green tea extract,” he adds. 

Nashai was founded in 2001 in collaboration with Vanderbilt University. The company has offices in Irvine, Calif., and Shanghai, China. It specializes in product research, development, and procurement for dietary supplements, over-the-counter medications, and active pharmaceutical ingredients