Scientific studies may give credence to food and beverage marketing programs, but first those studies must exist.
"In my opinion, marketing has gotten ahead of science in some respects," said Dr. Joy Dubost, principal nutritionist for PepsiCo, Inc., Valhalla, N.Y.
She said marketing and science need to keep a similar pace in the category of non-essential antioxidants when she spoke Feb. 28 in Chicago at "Food Technology Presents: Developing and Marketing Products for Consumer Health & Wellness," a conference run by the Institute of Food Technologists. Researchers now are seeking ways to measure the bioavailability of non-essential antioxidants, such as polyphenols found in fruits and vegetables.
Statistics from The Nielsen Co., New York, reveal financial reasons to promote antioxidant content in products. U.S. sales of products with antioxidant information on the label reached $1,429,027,558 for the 52 weeks ended Nov. 3, 2007, which marked nearly a 47% increase from $974,655,833 in the previous 52-week period and more than double the sales of $633,684,011 for the 52 weeks ended Nov. 5, 2005. The sales covered food, drug and mass merchandiser stores, excluding Wal-Mart.
Consuming antioxidants may neutralize sometimes harmful molecules known as free radicals, which may damage cells and may increase risk of atherosclerosis, cancer and other diseases, according to the U.S. Department of Agriculture.
Ms. Dubost said savvy consumers will want to know more about the effects of specific antioxidants. She divided antioxidants into two categories: essential and non-essential. Using essential antioxidants such as vitamin C, vitamin E, vitamin A, zinc and selenium in products may allow formulators to use "good source" or "excellent source" claims. Using them also may lead to structure function claims such as "Vitamin C, an antioxidant, promotes healthy skin and gums."
Non-essential antioxidants are available from multiple sources such as fruit, chocolate, wine and tea. Challenges arise when positioning non-essential antioxidants in products, Ms. Dubost said. They must stay active through the shelf life of a product. Formulators also should notice if non-essential antioxidants interfere with other components in a product.
Different ways exist to measure the antioxidant content in foods. Oxygen radical absorbance capacity (ORAC) is a popular one. A new term, cellular antioxidant activity (C.A.A.), appeared in a study on the subject reported online Sept. 29, 2007, in the Journal of Agricultural and Food Chemistry. Researchers at Cornell University in Ithaca, N.Y., developed the C.A.A. assay.
"There is an urgent requirement for more appropriate methods to evaluate the antioxidant activity of dietary supplements, phytochemicals and foods than the chemistry methods in common usage," the researchers said. "The C.A.A. assay addresses this need for a biologically relevant protocol."
The researchers said the C.A.A. assay is a more biologically relevant method because it accounts for some aspects of uptake, metabolism and location of antioxidant compounds within cells. Of all the fruits tested, the Cornell researchers found blueberries had the highest C.A.A. value, followed by cranberries.
Grapes, kiwifruit and wild blueberries were the best performers in results announced last year from a collaborative research effort that examined how antioxidant content affected blood antioxidant levels. This research was designed to shed insight into how ORAC scores translate into disease-fighting capabilities in humans. Ronald Prior, a chemist at the U.S.D.A. Arkansas Children’s Nutrition Center in Little Rock, Ark., was involved. Collaborators included researchers at the U.S.D.A. Human Nutrition Research Center on Aging at Tufts University in Boston; the U.S.D.A. Western Human Nutrition Research Center in Davis, Calif.; and the University of Maine in Orono.
A 2004 article in the Journal of Agricultural and Food Chemistry said cranberries contained 94.56 antioxidant capacity per gram, as measured by ORAC, to rank first among common fruits. Wild blueberries were second at 92.60 antioxidant capacity per gram.
Their antioxidant capacity links cranberries with benefits for heart, lung and cell health, among others, according to the Ocean Spray Ingredient Technology Group. A recent study at Tufts University and Boston University Medical Center found cranberry anthocyanins, a kind of antioxidant, are bioavailable, and that endothelial function improves following consumption of cranberry juice in patients with coronary artery disease. Ocean Spray, Inc. and the U.S.D.A. provided research support for the study.
According to Ocean Spray, the National Center for Complementary and Alternative Medicine within the National Institutes of Health funded 12 basic and clinical research projects to expand research on the health benefits of cranberries on urinary tract health, oral health, yeast viability and cardiovascular and inflammation. Most of these projects should be completed by 2010.
The antioxidant potency of beverages rich in polyphenols was the subject of a joint effort among researchers from the University of California at Los Angeles; the Rambam Medical Center in Haifa, Israel, and POM Wonderful, L.L.C., Los Angeles.
The study applied four tests of antioxidant potency, including ORAC, in apple juice, acai juice, black cherry juice, blueberry juice, cranberry juice, Concord grape juice, orange juice, red wine, iced tea beverages, black tea, green tea, white tea and pomegranate juice. An overall antioxidant potency composite index gave pomegranate juice the highest rating.
Food and beverage formulators may want to combine sources of antioxidants. The new Acai Mixed Berry beverage in the V8 V-Fusion line of products manufactured by the Campbell Soup Co. contains the juice of sweet potatoes, purple carrots, carrots, apples, white grapes, acai, blueberries and limes. The beverage is promoted for its content of essential antioxidants vitamin A, vitamin C and vitamin E.
Tea manufacturers apparently have benefited from consumer awareness of antioxidants, too. U.S. sales of liquid teas with antioxidant information on the label rose 64% to $385,919,960 for the 52 weeks ended Nov. 3, 2007, according to The Nielsen Co. Sales of tea bags increased more than 153% to $65,120,764.
The U.S.D.A. and other researchers used test-tube-based studies to measure antioxidants called flavonoids in black and green tea, Ms. Dubost said. Packages of the Lipton PureLeaf brand say the product has 72 mg of flavonoid antioxidants per 8 oz.