Superfruit Science

Many product designers are turning to superfruits to deliver health benefits, as well as flavor and color. Superfruits have higher levels of nutrients than average and often contain novel compounds not found in any other fruit. For example, the goji berry contains unique and very healthy compounds called Lyceum barbarum polysaccharides, which are found in no other food, says Lindsey Duncan, CEO, Genesis Today, Inc., Austin, TX.

Colorful promises

The superfood concept became popular around 2004, when Steven Pratt published his book, SuperFoods Rx, notes Deborah Payne, spokesperson for the U.S. Highbush Blueberry Council, San Francisco. The book lists blueberries as a superfood due to their high antioxidant levels and potential to reduce the effects of age-related loss in brain function.

Superfruits contain a variety of phytonutrients. However, many contain high amounts of flavonoids, such as anthocyanins, which give blueberries their deep color and also provide antioxidant and anti-inflammatory activity, says Payne.

Antioxidants are most effective when combined with other antioxidants, a scientific principle dubbed the antioxidant cascade effect, notes Ted Farnsworth, CEO, Purple Beverage Co., Fort Lauderdale, FL.

While conventional conceptions of superfoods tend to reflect overall nutrient density, Doles approach to superfoodsor superfruitsis unique in that it is on nutrient groups supporting particular health categories, such as bones, eyes, heart and others, says Nicholas Gillitt, nutrition research and labeling manager, Dole Nutrition Institute, Westlake Village, CA. For each category, a qualifying fruit must contain a minimum level of certain nutrients that have been grouped together because they have the same health benefit. For example, to be a superfood for the heart, a fruit must contain certain levels of any three of the following heart-healthy nutrients: potassium, fiber, folate, vitamin B₆, magnesium, vitamin C and antioxidant phytochemicals.

Superfruit claims are frequently challenged. Often, the superfruit claim is given to fruits that have not had clinical research performed on them, so the claims that are made for these fruits may not be based on sufficient scientific evidence, says Amy Howell, associate research scientist, Marucci Center for Blueberry and Cranberry Research, Rutgers University, Chatsworth, NJ. It is important to look for fruits that have positive clinical study results for things they are claiming ... such as cranberry and prevention of urinary tract infections, which is one of the best examples of a superfruit with good clinical trial evidence.

From everyday to exotic

Formulators should remember many superfruits are common, everyday fruits. Bananas are often overlooked when superfruit lists are developed. However, by all definitions, the banana is a superfruit, as it has been shown to assist in the alleviation of anemia, constipation, depression, heartburn, morning sickness and stress, says Tony Cantu, senior R&D technologist with iTi tropicals, Inc., Lawrenceville, NJ. The potassium in bananas keeps blood pressure in check, and thus helps prevent strokes. Potassium also assists with memory and brain power. FDAs authorized health claim for high-potassium foods, diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke, can apply to products that contain bananas at a sufficient level to deliver 10% of the Daily Value for potassium while meeting other stipulations of the claim regarding levels of fat, sodium and cholesterol.

Many rare, exotic superfruits, such as gac fruit (Momordica cochinchinensis), are making their way to the States. Grown in Vietnam, gac fruit is mainly used for food and medicine in many Southeast Asian countries, says Cantu. The seed pulp of this bright-red superfruit contains high concentrations of beta carotene, lycopene and unsaturated fatty acids.

The gac fruit contains more than 70 times the amount of lycopene found in tomatoes. Its omega-3 and omega-6 fatty acids assist with absorption of beta carotene, which is present at about 10 times the level found in carrots. Lycopene consumption is associated with a decreased risk of prostate cancer, while omega-3s are associated with a reduced risk of cardiovascualr disease, as well as cognitive development.

A spectrum of options

The fruits really making headlines are açaí, blueberries, cherries, cranberries and pomegranates. Exotics such as goji, guarana, mangosteen and noni are predicted to join this list soon.

One of the most thoroughly researched fruits on the market, the North American cranberry, has one of the most solid health claim foundations of all fruits, says Christina Khoo, principal scientist, research sciences, Ocean Spray Cranberries, Inc., Lakeville-Middleboro, MA. Research into cranberries health benefits can be traced back to the 1990s when the New England Journal of Medicine (1991; 324(22):1,599) identified a component in cranberries and blueberries that prevented the adhesion of certain E. coli bacteria in the gut. The unique A-type proanthocyanidins (PACs) in cranberry help prevent disease-causing bacteria from adhering to cells within the body, flushing them harmlessly away.

Blueberry is another all-American superfruit. A group of researchers led by James A. Joseph, research physiologist, Jean Mayer USDA Human Nutrition Research Center on Aging, Boston, developed a series of motor-skills tests for use on animals raised on a special blueberry diet, which revealed that they did significantly better than those that were not, he says.

Further, Joseph concluded that blueberries were actually able to reverse motor deficits in these aging animals. More remarkably, when mice that had been genetically altered to express Alzheimers were put on the blueberry diet, they did not experience memory loss.

The latest domestic fruit to gain super status is the tart cherry. Tart cherries contain similar amounts of antioxidants as blueberries, says Wendy Bazilian, author of The SuperFoodsRx Diet and co-owner of Bazilians Health Clinic, San Diego. Cherries get their red color from anthocyaninspowerful antioxidants that studies suggest may reduce inflammation and risk for heart disease. Cherries are also one of the few researched food sources of melatonin, a potent antioxidant that may help improve the bodys natural sleep patterns and aid with jet lag.

Recent University of Michigan, Ann Arbor, research presented at the 2008 Experimental Biology annual meeting found a cherry-rich diet significantly lowered blood cholesterol and triglyceride levels, abdominal fat, and insulin and fasting glucose levels, all major risk factors for heart disease and diabetes, notes Bazilian. The study also found that the cherry-rich diet reduced inflammation markers in the body up to 50%, she says. Scientists believe its the anthocyanins that are responsible for this anti-inflammatory benefit. Other studies indicate that anthocyanins may be beneficial for a range of inflammatory-related conditions, including arthritis.

Dissecting superfruits

Understanding how the compounds in superfruits function in the body, and validating the functionality in clinical trials, is important to keep consumer confidence high.

Superfruit success requires novelty, validated health benefits, convenience, controlled supply and promotion, says Karl Crawford, food business leader, HortResearch, Auckland, New Zealand. Our sensory and consumer science team studies how consumers respond to fruits and foods, providing valuable clues as to what consumers like and dislikewhat attracts them to a product and what makes them buy it. Our breeding teams can then access our collection of fruit germplasm and breed from these to create fruits that meet consumer demands for novelty, flavor and health.

We can also help discover and prove health claims associated with certain fruits, continues Crawford. We do this using hi-tech tools and techniques, including assays, to discover antioxidant function, anti-inflammatory properties, neurotransmitter effects, etc., and human clinical trialsbasically discovering and validating the health properties of fruit in humans.

Bridging the gap

Formulating with whole-fruit ingredients is a common way of delivering the super components of fruit. However, the functional components can be extracted and added to formulations, either alone or in conjunction with whole-fruit ingredients.

HortResearch studies how fruit and fruit compounds affect human mood and physical performance, as well as gut health and immunity. This work includes developing novel delivery processes for high-value formulations using micro- and nanoscale encapsulation techniques.

Sometimes, a food or beverage formulation is already based on a host of functional ingredients, and all it needs is a superfruit flavor to increase its appeal to todays health-and-wellness-seeking consumers.

Many of todays consumers are intrigued by the notion of culinary travel and fruits from faraway lands, says Steve Wolf, director, flavor applications, Robertet Flavors, Piscataway, NJ. In response, we are introducing a line of superfruit flavors. These flavors lend a healthful halo to foods and beverages, while also satisfying consumer desire for new flavor experiences.

Chemists with Virginia Dare, Brooklyn, NY, have also created superfruit flavors that enhance the taste of superfruit beverages. Such flavors have application in beverages that contain some superfruit juice and need a flavor boost.

Adding superfruits to foods isnt always easy from a flavor perspective. Because superfruits are often associated with functional foods, there can be bitter, astringent or even medicinal off notes that need to be masked, says Kathleen McNamara, senior flavor chemist, David Michael & Co., Philadelphia. The flavor of the fruit itself may even need to be enhanced.

Whole fruit forms

Superfruits are processed into juices, pastes or powders. For some of the superfruits, the processing has significant effect on their antioxidant activities, says Howell. For example, açaí physically deteriorates within 24 hours after picking. It should be processed into frozen pulp or dried powders to preserve freshness, she notes. On the other hand, the cranberry fruit maintains its bacterial anti-adhesion activity after it is processed into juice, sauce and powder, or even dried. Blueberries maintain their benefit on the aging brainimproving memory and coordinationwhen they are eaten fresh, frozen or freeze-dried.

Jim Saunders, director, tropiceutical sales, GCI Nutrients, Foster City, CA, adds: The greatest demand is for single-strength powders and extracts. These ingredients are standardized for the specific active compounds of a single fruit product.

There is also a demand for high-quality powders, such as freeze-dried and Refractance Windowdried, to retain antioxidant activity, nutrient content, color and flavor, continues Saunders. Refractance Window drying is the most energy-efficient dehydration method. It also reduces moisture content to under 1%, which prevents the growth of bacteria and mold, and preserves the beneficial compounds.

For enhanced piece identity, many product designers rely on individually quick-frozen (IQF) fruit, which usually contains no added sugar or preservatives. IQF fruit tends to readily separate, making it easy to weigh out the quantity during product manufacturing.

Infused frozen fruit is another ingredient form that provides piece identity. They do contain some added sugar and natural stabilizing agents. This inhibits ice-crystal formation and results in a fruit ingredient that does not completely freeze in frozen applications.

If whole pieces are not a priority, bases, purées and concentrates are all excellent choices. Most contain no added sugar, but because they are concentrated they have a high percentage of sugar. Purées often have significant piece identity.

Fruit-juice concentrates can be used alone or with the other fruit ingredients. Juice concentrate has a great deal of water removed from the product, which results in high Brix, but no piece identity.

Dried fruits come in sweetened and unsweetened form. Nutrient content after processing varies by fruit and supplier process. It is important to work closely with the supplier to confirm if the ingredient is packed with super components.

Superfruits go beyond providing water, fiber, vitamins and minerals, notes Bazilian. Superfruits possess the ability to not only potentially affect our health today, she says, but also promote health and reduce the risk of disease later.

Donna Berry, president of Chicago-based Dairy & Food Communications, Inc., a network of professionals in business-to-business technical and trade communications, has been writing about product development and marketing for 13 years. Prior to that, she worked for Kraft Foods in the natural-cheese division. She has a B.S. in Food Science from the University of Illinois in Urbana-Champaign. She can be reached at [email protected].