Antioxidant Beverages

It may be money that makes the world go ’round, but it’s oxidation that makes the world run down. The same cascade of reactions that converts shiny metal to rusty junk converts richly flavored and colored foods to rancid and pale-looking, and ravage the human body by causing an array of debilitating diseases and conditions.

“Consumers are becoming more and more aware of what an antioxidant is and the health benefits antioxidants can provide,” says Heather Biehl, senior scientist, HITS, WILD Flavors, Inc., Erlanger, KY. “Because of the increased awareness, the interest of consumers in antioxidants is growing and the beverage market is responding to consumers’ interest by developing more products with the added benefits of antioxidants.” Beverages are a key vehicle for these compounds.

Quantifiable results

Oxygen radical absorption capacity (ORAC) is a means of expressing the antioxidant power of a given food. Developed in 1993, the ORAC test compares a substance’s ability to quench free radicals to that of a standard—a vitamin E derivative called Trolox or gallic acid. ORAC scores are reported in Trolox equivalents (TE) or gallic acid equivalents (GAE) per unit weight of sample.

Other tests have been developed, including ferric ion reducing antioxidant power (FRAP) and Trolox equivalence antioxidant capacity (TEAC) assays. Results from these tests are not directly comparable with ORAC values. While some experts would argue the ORAC assay produces misleading results, a 2007 government report, “Oxygen Radical Absorption Capacity (ORAC) of Selected Foods,” states that the ORAC assay is “considered by some to be a preferable method because of its biological relevance to the in vivo antioxidant efficacy.”

A-C-E in the hole

Several vitamins act as antioxidants. The first, vitamin A, may occur in several active forms, including the alcohol form (retinol), the aldehyde form (retinal) and an acid form (retinoic acid).

Vitamin A is a member of the carotenoid family, a group of roughly 700 oil-soluble polyunsaturated compounds displaying a range of colors from bright-yellow to deep-red, depending on the number and position of their double bonds. Carotenoids that terminate with a cyclic hydrocarbon group are called carotenes and include compounds like lycopene. Xanthophylls such as lutein and zeaxanthin possess an additional oxygen-containing functional group.

Five double bonds and a free hydroxyl group make vitamin A susceptible to oxidation during processing and/or shelf life—especially when pH is below 5. Developers, therefore, often turn to beta carotene. A more-stable compound than retinol, beta carotene is converted to vitamin A in the body at a rate of approximately 6:1. And, while Vitamin A toxicity (upper limit 3,000 mcg per day) can cause birth defects, beta carotene’s only known side effect from overdosing is yellowing of the skin.

Vitamin C, ascorbic acid, is a crucial element in the production of collagen, norepinephrine and carnitine synthesis, and cholesterol metabolism. A strong antioxidant, vitamin C is known for prohibiting oxidative reactions by sequestering the metals that catalyze them, and helping prevent formation of free radicals in cellular fluids by donating hydrogen atoms from its two hydroxyl positions. Vitamin C also rejuvenates vitamin E to an antioxidant form.

Vitamin E is a name that actually encompasses eight compounds: four tocopherols and four tocotrienols, the most stable and biologically active of which is alpha-tocopherol. An important and powerful antioxidant, protecting cell membrane lipids from oxidation by donating electrons to free radicals and stopping oxidative chain reactions, vitamin E has also been shown to increase high-density lipoprotein (HDL) levels and prevent low-density lipoprotein (LDL) oxidation.

Enzyme essentials

In addition to these three vitamins, several minerals play crucial roles in the composition of antioxidant enzymes. Selenium, for example, is a key element in antioxidant enzymes glutathione peroxidase, an alpha-tocopherol activity enhancer, and thioredoxin reductase, a catalyst for the regeneration of vitamin C from the oxidized form. Other minerals function as elements of antioxidant enzymes, as well—zinc and copper as part of superoxide dismutase, and iron as part of catalase.

Enzymes are often assisted by compounds called coenzymes. One such helper-compound is coenzyme Q₁₀ (CoQ₁₀), comprised of a benzoquinone functional group and 10 isoprene units. It’s known as ubiquinone and is found in all animal cell membranes and lipoproteins. An excellent electron donor and acceptor, CoQ₁₀ helps protect membranes and LDL cholesterol from peroxidation. In addition to neutralizing free radicals, CoQ₁₀ can also regenerate alpha-tocopherol from its oxidized state.

“When looking at fat-soluble antioxidants, one of the best is CoQ₁₀, which has a dual function for energy,” says Rodger Jonas, manager, new business development, P.L. Thomas & Co., Inc., Morristown, NJ.

Once limited to use as a supplement, CoQ₁₀, backed by self-affirmed GRAS status, is finding application in beverage systems throughout the world. In 2007, CoQ₁₀ was a component of six newly introduced energy drinks in the United States, a continuation of the steady increase in such introductions since 2004, when only one such product was released.

Superfruit strikes again

American consumers have long known about the power of “an apple a day.” However, a growing list of fruits is recognized for extraordinary health benefits with the title “superfruits.” Growing awareness of health benefits from familiar fruits has elevated them to “superfruit” status. “There is growing interest in superfruits,” says Ram Chaudhari, senior executive vice president and chief scientific officer, Fortitech, Schenectady, NY. “Apple, cranberry and blueberry are very popular in beverage applications at this time.”

Açaí is harvested in the Amazon from what natives often call the “tree of life,” a reference to the antiaging effects of its antioxidants, including vitamin E, vitamin C, gallic acid, epicatechin, anthocyanins, procyanidins and protocatechuic acid. Açaí berries deliver one of the highest known antioxidant strengths of any food, approximately 60% stronger than the No. 2 superfruit, pomegranate.

With ORAC values of 10,500 µmol TE per 100 grams of juice, pomegranate provides an array of antioxidants, including vitamins A (from alpha and beta carotene), C and E, as well as ellagic acid, gallocatechins, prodelphinidins, delphinidin, cyanidin, pelargonidin and punicalagin. The most-abundant of the lot, punicalagins, are hydrolysable polyphenol compounds called tannins that have been shown to increase blood plasma antioxidants by over 30% as quickly as 30 minutes after consumption.

Future for-tea-fication

Enjoyed for centuries, tea consumption worldwide is second only to water. Today, health-conscious consumers in America are embracing tea as a source of antioxidants, particularly polyphenols. Fresh tea leaves’ primary polyphenols are epigallocatechin gallate (EGCG), epigallocatechin, epicatechin gallate, and epicatechin. Polyphenol levels vary: Green teas carry 30% to 40%, and black teas (fermented and oxidized green tea) have between 3% and 4%. Oolong teas are partially fermented, and fall somewhere between green and black.

Today, tea extracts are recognized as valuable sources of these powerful antioxidants, despite potential challenges of flavor and browning effects. “Proprietary extraction technologies from Wild Flavors produce clean tasting, water-soluble extracts, with little to no color, and all of their antioxidant health benefits,” says Biehl. “Formulators can incorporate these antioxidants at high use rates without compromising product quality.

Clearing the hurdles

Beverages’ convenience makes them a great choice for consumers looking for nutrition on-the-go. Large serving sizes allow developers plenty of room for “per-serving” levels of their ingredients. But addition is not always as easy as it sounds.

Most beverages are aqueous in nature, so encapsulation can provide dispersability for oil-soluble materials such as beta-carotene and vitamin E, ensuring optimal distribution and stability, while limiting effects on finished-product characteristics. Developers should, however, be certain the encapsulation coating material is suitable for their product. Gelatin-based coatings, for example, can interact with polyphenols in fruit juices and cause sedimentation.

Emulsion technology can also make oil-soluble vitamins suitable for some water-based applications. “While standard emulsions will be cloudy,” Biehl says, “WILD Flavors’ new patent-pending microemulsion technology results in clear emulsions.”

Charlotte Fredrickson, DSM Nutritionals, Parsippany, NJ, suggests an additional approach to eliminating cloudiness. “While other solutions to this problem are in the use of emulsifiers, which can have organoleptic issues, DSM was able to develop a vitamin E formulation based on modified food starch only,” she says.

“The unique technique is not the spray-drying step but the emulsification step,” says Peter Schuler, technical marketing, human nutrition & health, DSM Nutritional Products Europe Ltd., Basel, Switzerland. “Usually, oil-in-water emulsions have in their discontinuous phase (the oily droplets in the water phase), particles with 100 to 500 nm diameter. The new technology produces particles less than 100 nm. The small droplets are no longer visible to humans and, therefore, the liquid looks clear. They no longer cream up or sediment in a beverage.”

Jonas reports that fat-soluble CoQ₁₀ can be added to beverages with no affect on clarity—despite a slight orange tint—by means of nanotechnology.

Dispersion isn’t the only problem. Vitamin C’s strength as an antioxidant is paralleled by its sensitivity to heat and oxygen. High affinity for metals and minerals can also lead to oxidation of ascorbic acid, as can exposure to light. When formulating with vitamin C, developers may consider protective technologies such as encapsulation and overages, i.e., adding more than needed to account for losses during processing. But be careful. “At high levels, vitamin C can act as a pro-oxidant,” Biehl notes. “Too much vitamin C will cause browning. It’s why many vitamin-enhanced waters are in blue bottles to conceal off-color development.”

Extracts can provide a convenient means of delivering the benefits of superfruits to systems where whole fruits are simply not feasible due to solubility issues and interactions which can create issues surrounding stability, sensory properties, color and mouthfeel of the finished products.. “Superfruit extracts can be strongly colored or astringent,” Biehl says, “possibly limiting the products’ application.”

Whether in the form of superfruit or tea, vitamins or other antioxidant-rich ingredients, as consumers gain a better understanding of the benefits of antioxidants in the diet, logical delivery vehicles like beverages will undoubtedly continue to grow in popularity.

R. J. Foster is a wordsmith with a B.S. in food science from the University of Wisconsin-Madison and over 15 years of experience in the food industry. He can be reached through his website, wordsmithingbyfoster.com.

Market Snapshot

The Great Superfruit Surge

Exotic fruits are quickly showing up on consumers’ shopping lists. In fact, according to Datamonitor’s Productscan Online database, Naples, NY, six exotic superfruits, açaí, goji, mangosteen, noni, pomegranate and seaberry, were used in over 500 new SKUs in 2006. The trend continued through 2007, with over 60% more new product introductions compared to 2006.

Self-Serve Nutrition

So, you’re interested in antioxidant beverages, but can’t bear to part with your favorite drink? Garrett Lindeman, Ph.D., president and CEO/CSO, Gourmetceuticals, Big Horn, WY, offers an interesting solution.

“Changing the antioxidant into a powdered form or tablet allows the consumer to easily carry the antioxidant in a purse or pocket to add into a juice or milk, etc.,” says Lindeman. “Antioxidants in a powder or tablet form would be convenient for the consumer to access regardless of their location, or during travel.”

Beyond consumer convenience, such a format would present advantages to antioxidant suppliers. “This form would have a longer shelf life and also allow the manufacturer to make different shelf presentations, such as placing it next to a checkout register for a consumer to purchase,” Lindeman adds. “The powder or tablet form would also be more cost effective for the manufacturer to export or ship.”