The industry has been focusing on natural sweeteners, and the Coca-Cola Company is partnering with a notable supplier to develop and introduce what they term is the “industry’s first natural, zero-calorie sweetener”--rebiana comes from the leaf of the stevia plant and will be found in Coca-Cola’s family of beverages and as a food ingredient.


As the beverage market evolves, demand for functional beverages with health and wellness benefits is increasing. However, formulating these new beverages to deliver the health benefits with a sensory experience that consumers require is a constant challenge. New trends for flavors, sweeteners, ingredients and processing variables add to the complexity of creating a beverage system.  

As formulators develop new health and wellness beverages, key considerations must be kept in mind when using ingredients to help deliver those benefits.  

Acid Tongues: Acidifiers and Sensory Considerations

Acids can play several roles in beverage systems, including minimizing the amount of heat needed for processing, increasing microbial stability, inhibiting oxidation and heightening the effectiveness of preservatives. Yet, acids also can introduce sourness that overwhelms a formulation’s flavor or negatively impacts other sensory characteristics, such as astringency, aftertaste or mouthfeel. 

Consequently, beverage formulators must critically consider all aspects of a new product, such as nutritional targets, flavor profiles and the processing and packaging aspects when formulating with acids. For example, citric and tartaric acids provide a sourness that disappears quickly, whereas the sourness of malic, fumaric and acetic are more persistent. 

In addition, each acid carries unique flavor characteristics:
* Acetic acid--can be reminiscent of vinegar and quite pungent.
* Malic acid--known for imparting a fruity or “green apple” sourness.
* Fumaric acid--has a clean, dry taste. 
*  Lactic acid--often has a slight dairy aroma.
* Phosphoric acid--used in many colas and low-pH beverage systems; creates more of a burning taste due to its strength. 
* Citric acid--used widely, because it delivers a bright, clean and refreshing taste.

Buffers and Sweetening Systems

Buffers are generally made of a weak acid and its conjugate base, such as citric acid and sodium citrate. In beverages, buffers keep pH in the range where the ingredients are most effective and also can help eliminate changes in flavor or color characteristics, when pH levels are adjusted. For example, a pH level of 4.2 is considered optimum for aspartame. By using buffers to maintain this range during processing, the aspartame will not significantly degrade and negatively impact the shelflife or sensory experience of the finished product.

Sweetening systems are often chosen based on cost, labeling and overall sensory attributes. Beverage formulators must first decide whether they would like to target nutritive or non-nutritive sweeteners, a decision usually based upon caloric or labeling restrictions for the target beverage. Commonly used nutritive sweeteners for beverages include sugar, sucrose and/or high-fructose corn syrup. For non-nutritive sweeteners, U.S. formulators may try aspartame, acesulfame potassium (ace-K), sucralose, saccharin and neotame. More recently, formulators have been focusing on natural sweeteners, such as stevia and luo han guo (Monk’s fruit), to reduce sugar content while maintaining sweetness. (Editor’s note: At least two suppliers have made a self-affirmed determination of GRAS for stevia  “Rebaudioside A, purified from Stevia rebaudiana (Bertoni),” and have notified the FDA. As of June 2008, the FDA’s CFSAN/Office of Food Additive Safety listed the status of these ingredients as “pending.” See www.cfsan.fda.gov/~rdb/opa-gras.html.”) Fruit juice concentrates also have been used to add sweetness, flavor and color, while touting a healthier label. 

Balancing a product's sweetness and acidity is important to the consumer’s taste experience. For example, “when using aspartame, sucralose and/or neotame, which all have prolonged sweetness, malic or lactic acid may work the best to balance flavor, because they each have a more persistent sour note,” states Steve Rittmanic, president, Nutrifab LLC. “In addition to tartness, acids may also enhance the flavor character. Many times, citric may be added to a yogurt smoothie or fruit drink-type formulation to round out the tartness perception.” Rittmanic also notes that “identifying the correct combinations of ingredients to provide function during processing and end-product flavor characteristics for consumers is what makes beverage formulation challenging.”

Formulating in the Health: Vitamins

Vitamins are organic compounds that cannot be synthesized in sufficient quantities by the body, so they must be obtained from the diet. In beverage formulations, a variety of vitamins is considered for inclusion. Beverage formulators need to determine which vitamins they are going to fortify with and at what levels. Knowledge of intended process, packaging and pH ranges also are required to anticipate possible vitamin breakdowns and interactions.

Vitamins A, D and E are oil-soluble, so a formulation must begin with emulsions.  Individually, these vitamins play unique roles:
* Vitamin A--helps with cell reproduction, eye health, fetal growth and reproductive function.
* Vitamin D--regulates the reabsorption of calcium in the kidneys, bone mineralization, parathyroid hormones and immune function. 
* Vitamin E (alpha-tocopherol)--protects cell membranes from oxidation.
Since beverages are typically water-based systems, water-soluble vitamins, such as B-complex and C, are easier to use. B vitamins may exhibit flavor issues when added to a beverage. One approach is to use reduced levels (10-20% daily value) of B vitamins to circumvent potential problems.
* Vitamin B1 (thiamin)--functions as the coenzyme thiamin pyrophosphate, part of the glucose oxidation process. It is heat-stable in acid beverages, but concentrations need to be increased if used in a product at neutral to alkaline levels, due to its instability at higher pH. 
* Vitamin B2 (riboflavin)--is required for cell growth. It also is heat-resistant, but not light-resistant, so the type of final package may have an impact on its stability. 
* Niacin--is required for glucose oxidation and respiration in tissues. It is stable to oxidation, light and heat.
* Vitamin B6 (pyridoxine, pyridoxamine and pyridoxal)--is required for metabolism.
* Pantothenic acid also may provide tolerance to stress, such as intense exercise.
* Vitamin B12--is active in carbohydrate and fat metabolism.
* Vitamin C (ascorbic acid) -- is a strong antioxidant and is critical to the formation of collagen for maintenance of connective tissue and skin. Since it is easily lost to oxygen, reducing oxygen in the beverage is a high priority.

Antioxidants: Powerful Benefits

In the past year, beverage manufacturers have expressed increasing interest in phytochemicals. Much of the focus in beverages has been on antioxidants, which defend the body against free radicals formed during exercise and stress. 

Anthocyanins, natural red-to-purple pigments found in fruit, possess antioxidant properties, as well. Blackberries, blueberries and elderberries all contain anthocyanins and provide a dual role of providing coloration and antioxidant protection for beverage formulations. Carotenoids, including B-carotene and lycopene, are another natural source of antioxidants. These natural pigments are primarily used in fruit/vegetable beverage blends.

Lastly, polyphenols, found in teas, have long been recognized for their antioxidant properties in Asian cultures. Tea and fruit blends have become quite popular in the U.S., because they reach a consumer need for the healing properties of antioxidants mixed with the desired “pick-me-up” of a caffeinated beverage.

Stabilizers: Appearance is EverythingChoosing the correct stabilizer for a beverage may make the difference between consumer acceptance or failure. Stabilizer systems can provide thickness, viscosity and/or act as a fat mimetic. When deciding which stabilizer or blend to use, a formulator must first understand the intended manufacturing process. Processing temperatures and homogenization pressures may be necessary to activate the stabilizer and/or create the desired mouthfeel. 

Starches are a common stabilizer in cultured dairy beverages. They tend to be the least expensive forms of stabilization and are relatively easy to use. However, they may impart non-dairy flavors to a beverage when used at higher levels.

Whey proteins and milk protein concentrates are also effective stabilizers for cultured dairy beverages. A key consideration when using proteins is the amount of heat used in the process. Under certain specific conditions, heat treatment and/or shear will denature the proteins, resulting in greater water-binding properties. This water binding contributes to a smooth mouthfeel and prevents syneresis.

Non-fat dry milk is another commonly used dairy ingredient for dairy beverages; it adds a more opaque, creamy flavor and appearance to a beverage. Dairy ingredients may increase overall cost, so balancing function and cost may be best achieved through blending dairy ingredients with hydrocolloids to create the targeted finished-product characteristics.

Natural gums are used in stabilizer systems. Gum Arabic, derived from acacia trees in Africa, is a functional gum and a good source of soluble fiber. Gum Arabic dissolves in cold water and serves as an emulsifier, to create a suitable mouthfeel without gelation. “Because more beverage companies are looking to add fiber to their products, gum Arabic may be a good solution because it is natural, functional, nutritional and palatable,” said George Sanderson, an independent hydrocolloid industry consultant.

(Editor’s note: Although most do not possess emulsifier capabilities, other low-viscosity options for fiber fortification include hydrolyzed guar gum, certain modified starches, resistant maltodextrin, low molecular weight methylcellulose, corn fiber gum [an arabinoxylan] and certain arabinogalactans, among others.)

Carrageenan, another common stabilizer, thickens during beverage processing by creating a gel and is often the gum of choice for suspension of cocoa in chocolate milk. Carboxymethylcellulose comes in a variety of different viscosity ranges and provides clarity. Xanthan gum may be of assistance in beverages with very low pH levels and can be a good choice in the suspension of ingredients in certain beverages.

Historically, pectin has been used in fruit preps to provide a gelled texture. “[Certain] pectins themselves are calcium-sensitive, which is why they are an excellent way to create creaminess in dairy-based beverages,” explains Louise Wicker, Ph.D., professor of food chemistry, University of Georgia. Wicker’s laboratory has been successful in using pectins in combination with whey proteins to create yogurt beverages with improved mouthfeel and viscosity characteristics.

Growing on Consumers: Probiotics

While yogurt and yogurt drinks have long enjoyed their position as healthy foods, the launch of new products, including Dannon’s Activia and Yoplait’s Yo-Plus probiotic yogurts, have provided new health and wellness benefits that consumers have responded to with sales in the marketplace. According to Nancy Auestad, vice president—regulatory affairs at Dairy Management Inc. (DMI), “The scientific evidence that probiotic-rich foods in the diet may lead to overall improved health continues to emerge. Research shows that some types of probiotics help support gastrointestinal function and others help support the immune system.”

However, developing beverages containing probiotics presents significant formulation and processing challenges. The pH of many beverages is specifically intended to eliminate bacterial growth. Plus, hot-fill and retort processing are, by definition, not “bacteria-friendly,” whether the organism is a pathogen or a probiotic. For these and other reasons, dairy-based beverages remain the primary vehicle to carry probiotics and their benefits. Beverages typically begin at a neutral pH (that of pasteurized milk), then move to a pH of around 4.4 after culturing. Typically, probiotic strains are added at this point. 

The chilled distribution systems for dairy products allow for live and active cultures to survive and still maintain high-quality end products. The dairy environment may have additional benefits to the cultures. According to Greg Miller, Ph.D., executive vice president of research, regulatory and scientific affairs at the National Dairy Council, “Researchers are investigating why dairy could be an ideal delivery vehicle for probiotics, as components in milk may turn on certain genes in probiotic bacteria, enhancing their activity and benefit to consumers.”

Putting Muscle Behind a Beverage: Proteins and Amino Acids

While the amino acid taurine is nearly a standard ingredient in many energy drink formulations, other amino acids commonly found in beverages include L-glutamine and the branched-chain amino acids leucine, isoleucine and valine. While these latter amino acids are often included for their benefits in muscle recovery and repair (e.g., as in the Accelerade and Designer Whey products), they are increasingly appearing in more mainstream beverages, such as Special K2O Protein Water and Starbucks’ new “nourishing blends” beverages (launched in July 2008).

Protein can be an important part of any nutritionally focused beverage for a variety of consumer targets. While specific needs, such as flavor profile, processing and final packaging, will influence the choice of protein source, beverages typically are either dairy- (whey or casein) or soy-based.  

“Whey proteins are often the preferred protein source for ready-to-drink beverages, due to their excellent nutritionals, clean flavor and unique ability to deliver a clear, protein-fortified beverage,” said Alan Reed, senior vice president of manufacturing and ingredient marketing at DMI. Whey protein has the ability to remain soluble in acidic conditions (a pH range of 2.8-3.5). Since hot-fill is a typical thermal process for acidic beverages, whey proteins can withstand high temperatures and continue to deliver a clear, satisfying end-product with protein concentrations up to 10%. For these reasons, most fruit-based beverages can be fortified with whey protein and have a low pH level. 

Successfully formulating a new generation of health and wellness beverages requires a complete technical knowledge of the ingredients used, their interactions with each other and the impacts of processing treatments. Incorporating ingredients into the formulation at the right time and in the correct manner to preserve the integrity of the finished product is critical. By balancing all of these elements, formulators will be able to succeed in developing healthy, tasty and successful new beverage products. pf

Mary Higgins, MRH Consulting, is a consultant in the food and beverage industry. Additional information and resources for this article have been provided by Dairy Management Inc., www.innovatewithdairy.com.

SIDEBAR: avors

ADDED FLAVORINGS ARE OFTEN KEY TO CAREFULLY CRAFTED BEVERAGES. THEY DE-EMPHASIZE UNDESIRABLE FLAVORS AND OFFER A FAMILIAR NOTE TO SOME CONSUMERS, WHILE APPEALING TO OTHERS DESIRING SOMETHING UNIQUE.

AMONG FLAVORED STILL DRINKS INTRODUCED IN NORTH AMERICA SINCE JANUARY 1, 2007, THE TOP 10 MOST POPULAR FLAVORINGS WERE ALL FRUITS, LED BY LEMONADE, REPORTS DATA FROM MINTEL GLOBAL NEW PRODUCTS DATABASE (GNPD). ADULTS AND KIDS ALIKE WANT FAMILIARITY. FOR EXAMPLE, HONEST TEAS LAUNCHED HONEST KIDS ORGANIC THIRST QUENCHER VARIETY PACK IN THE KID-FRIENDLY FLAVORS OF “GOODNESS GRAPENESS,” “BERRY BERRY GOOD LEMONADE” AND “TROPICAL TANGO PUNCH.”

HOWEVER, FURTHER DOWN THE LIST, LESS COMMON, BUT MORE INNOVATIVE, FLAVORINGS APPEAR. CANADA’S ELIXIR CARBER INTRODUCED A MAPLE & GROUND CHERRIES NON-ALCOHOLIC APERITIF UNDER THE ORFORD BRAND. THE APERITIF CAN BE SERVED WITH VODKA, RUM, WINE, MINERAL WATER OR LIME, ACCORDING TO MINTEL, AND IS A “WONDERFUL COMPLEMENT TO ANY CHEESE PLATTER.” IN ANOTHER FLASH OF CREATIVITY, THE COMPANY’S MOE’S MAPLE & ANISE NON-ALCOHOLIC DIGESTIVE IS A BEVERAGE TO BE SERVED ICE-COLD ALONE OR WITH RUM OR VODKA. IT CAN “BE USED AS A MARINADE, TO ENHANCE SOUPS OR TO ADD FLAVOR TO SEAFOOD OR WHITE MEAT. THE PRODUCT CAN BE USED TO MAKE SORBET OR DRIZZLED OVER ICE CREAM AND OTHER DESSERTS,” EXPLAINS MINTEL’S GNPD.

THEN, THERE IS THE MATTER OF NUTRITIONALLY INNOVATIVE BEVERAGES NEEDING A TOUCH OF “HELP.” READY-TO-DRINK, QUINOA GRAIN-BASED BEVERAGES FROM THE COMPANY QUINOA WERE JUST INTRODUCED UNDER THE QUINOA GOLD BRAND. THE COMPANY NOTES, “QUINOA IS A GRAIN THAT WAS USED BY THE INCAS OF THE ANDES MOUNTAINS IN PERU AND BOLIVIA AND CONTAINS NINE AMINO ACIDS, FIBER, PROTEIN, MANGANESE, MAGNESIUM, IRON, NIACIN, ZINC, RIBOFLAVIN AND VITAMINS AND MINERALS.” IT DIFFERENTIATES PRODUCTS IN THE LINE BY THE FLAVORINGS: DARK BERRY, MANGO PASSION AND PINA COLADA. THE INGREDIENTS LEGEND IN DARK BERRY READS, “AGAVE NECTAR, ORGANIC QUINOA, NATURAL FLAVORS, CITRIC ACID.”
—CLAUDIA D. O’DONNELL, CHIEF EDITOR