Super fruits?

Certain fruits are undeniably good at grabbing headlines. Packed with antioxidants and fibres and brimming with sex appeal, so-called 'super fruits' - from goji berries to cranberries - are loved by celebrities and nutritionists alike. But will they prove equally adept at demonstrating their myriad health benefits to regulators as the Nutrition and Health Claims Regulation kicks in?

Frustratingly for companies looking to develop products featuring these fruits, there is as yet no clear cut answer, although it is likely that the term 'super fruit' could itself be regarded as an implied health claim under the new Regulation and, therefore, banned unless it is accompanied by an approved health claim. As for article 13 claims (those supported by generally accepted science that don't refer to reducing the risk of disease), the expectation is that several generic fruit-based claims will be approved.

Sabine Nafziger, of European food trade association CIAA, says. "There are likely to be three levels of fruit claims in the article 13 list. First, generic ones about diets rich in fruit and vegetables being good for your health; second, specific claims about specific fruits, such as cranberries, and urinary tract infections; and third, more detailed claims about the health benefits of specific bioactive substances in fruits."

So far, so good. However, companies wishing to make bolder claims about the potential of fruits to reduce the risk of cancers, heart disease or Alzheimer's, will have to submit dossiers to the European Food Safety Authority (EFSA) for scrutiny under a new authorisation procedure enshrined in article 14 of the Regulation. And the evidence supporting some of these claims is more sketchy, experts admit.

While EFSA will consider animal and epidemiological studies when it scrutinises dossiers, human trials will also be required which, in the case of certain cancers, could present real challenges, says Alan Crozier, professor of plant biochemistry and human nutrition at the University of Glasgow, UK.

"There have been some encouraging studies on rats," he says, "but to get some really decisive evidence about humans, studying biomarkers is not really enough. Ideally, you would need to control the diet of an extremely large number of people for years and years to see if they develop cancer. And that is prohibitively expensive."

Bioavailability is another critical factor, he adds. "It's all very well testing antioxidants in the test tube but do they actually get to the right place in our bodies to exert a meaningful effect? Further research is required to establish which of the flavonoids and phenolic compounds and their related metabolites gain access to appropriate cellular sites in the body to exert their biological effects." For example, while rat studies looking at the effects of blueberries or blackcurrants on brain function have demonstrated that active components of fruits are getting through the blood-brain barrier, human studies have been less conclusive, he points out.

In the meantime, says Crozier, consumers do not always know what they are getting. "My concern is that people see two drinks from the same fruit and think they are both as beneficial. They may not be. Take pomegranate juice. Some brands have a far higher antioxidant activity than others."

Derek Stewart, a scientist at the Scottish Crop Research Institute, also agrees that further research is needed to substantiate the more "opportunistic claims" about so-called super fruits and that more cash is required to support breeding programmes that produce fruits with the highest levels of bioactive components.

"The reactive oxygen theory of degenerative disease provides a potential rationale for claims about berries and generates testable hypotheses, but the scientific literature is in many cases contradictory," he says. For example, though some human studies exploring the effects of berries on biomarkers of cancer risk (such as levels of oxidised DNA in peripheral blood mononuclear cells or the number of pre-cancerous lesions in the bowel) have revealed positive results, others have shown them to have no impact, he claims.

the antioxidant myth?

While some better researched fruits, such as cranberries, are proven to be effective in tackling everything from urinary tract infections to gum disease and E. coli, most claims about fruits refer more generally to their high antioxidant content.

By mopping up free radicals (destructive compounds that are natural byproducts of respiration), antioxidants are believed to reduce the risk of diseases associated with oxidative stress, from heart attacks to strokes, cancer, arthritis, Parkinson's and Alzheimer's.

Not everyone is convinced of the power of fruit to ward off disease, however, especially when its bioactive ingredients are delivered in the form of dietary supplements. One such sceptic is Dr Lisa Melton, who provoked a storm of controversy last year with a paper in New Scientist alleging that "at best, antioxidant supplements do little or nothing to benefit our health. At worst, they may even have the opposite effect"

Despite compelling epidemiological evidence suggesting a link between fruit consumption and a lower incidence of chronic disease, the results of human intervention trials with antioxidant supplements are mixed, claims Melton. "They knock the wind out of free radicals in a test tube. But once inside the human body, they seem strangely powerless."

As for polyphenols, "it is not clear that they are absorbed into the bloodstream and if they are they are swiftly metabolised". By contrast, polyphenols, carotenoids and vitamins contained in whole fruits and vegetables are bound into fibrous material and therefore stay longer in the stomach and colon (where they can neutralise free radicals), she claims. There is also some evidence that the nutrients in fruits do not work in isolation but in concert with each other, explaining why trials that isolate specific bioactive extracts are often inconclusive, she says.

While Melton's thesis has been criticised by scientists, there is little evidence her cynicism has dampened the enthusiasm of consumers for fruits or antioxidant supplements, points out Dr Toni Gill, a nutritionist at the UK Medical Research Council. And neither should it, she says. "It is true that we do not fully understand how fruit compounds work in our bodies. What we do know is that eating a wide variety of fruit and vegetables increases your chance of getting the full range of nutrients and phytochemicals that are important for health. Fruit is good for you."

Substantiating health claims about fruit is important, says Karl Crawford, business leader at New Zealand-based fruit research organisation HortResearch. "But it's not the be all and end all. We're looking at how fruits could improve gut health, immunity and inflammatory conditions; physical performance and fitness; and mental well-being and, yes, more research is definitely needed in all of these areas.

"However, fruit already has a head start over most other functional foods in that consumers trust it. They understand it. They will try a new fruit even when they are suspicious of other new things, because they know that it's likely to be good for them."

There are also exciting opportunities to tailor new fruits to meet consumer requirements in terms of health and sensory perception, he says. "We have huge databases detailing genes responsible for coding specific traits in fruits. We use this knowledge to speed up the traditional plant-breeding process to produce fruits with higher levels of bioactive compounds, unusual coloured flesh, particular fragrances and textures or even edible skins. The opportunities are endless."

Given our warm feeling towards fruit, if an exotic variety captures the public imagination, or an old one becomes sexy again, thanks to a new study or celebrity endorsement, it can establish itself in the market more quickly than other products, observes Julian Mellentin from the Centre for Food and Health Studies. "Pomegranates have gone from being obscure to ubiquitous in the space of five years."

Despite the media hype, research from Mintel's Global New Products Database (top right) reveals that while cranberries, blueberries and pomegranates are making appearances in everything from muffins to smoothies, cereals and yoghurts, the number of new product launches in Europe involving goji, acerola, açai, mangosteen and noni is surprisingly small.

This is partly because things always take longer to get to market than you think and partly because they are not as versatile as other fruits, says Doug Mackay, general manager at J O Sims, a UK-based firm specialising in fresh and frozen fruit and fruit ingredients. "Some of the more exotic fruits don't taste great on their own, so they are typically used in blends with other fruits. The recent uncertainty about the regulatory status of goji berries has also held back developments in this area." That notwithstanding, Mackay is confident that double-digit growth in J O Sims' ingredients sales will continue as manufacturers look for ways to add health and functionality to their products and appeal to consumers' desire for 'natural' ingredients.

As for what customers want from super fruits, provenance is as important as health claims, says Mackay. "Customers want to know what scientific research there is, ORAC (oxygen radical absorbance capacity) values and so on, but they also want the story - where does the fruit come from? Is it sustainable?"

If you're looking for a super fruit that's got a great story, health credentials and taste, look no further than blueberries, which are increasingly featuring in smoothies, juices, cereals, snacks, desserts and cakes, with more than 544 new product launches in Europe since 2005.

While they have clearly benefited from the super fruits craze, they are also perceived as a premium product, says Mike Nicholas at the Wild Blueberry Association of North America. "People also like the idea of wild as opposed to cultivated blueberries."

Olives - the cornerstone of the Mediterranean diet - may also lay claim to super fruit status in future, predicts Christian Artaria, marketing director at Italian plant extracts supplier Indena. However, the phenolic fraction of olive fruits is very complex with composition heavily dependent on cultivar, cultivation and harvesting parameters, he says. "We are trying to make a direct correlation between the specific phenolic profile of our pulp olive extracts and the results we are looking for." Bilberries are equally promising, he says: "Almost 50 peer-reviewed papers have been published on our standardised bilberry extract. It was originally prescribed for venous insufficiency [when veins do not channel the flow of blood adequately], but its indications rapidly expanded to include retinopathy and ocular disturbances, while evidence is accumulating that it can be useful also for cognitive disorders and a host of degenerative conditions."

The future for cranberries is equally bright, predicts Arun Hiranandani, marketing boss at Ocean Spray's ingredient technology group.

One of the most researched fruits on earth, the cranberry has long-established links to preventing infection in the urinary tract, mouth and stomach, while its high antioxidant quotient could also make it a powerful nutritional weapon in the fight against heart and lung disease and certain cancers, he says. Ocean Spray cranberry juice also clinched the top spot in a study by Glasgow's Professor Crozier that compares the phenolic content of 13 fruit juices in the UK market.

Particularly encouraging is the level of interest from central and eastern Europe, he adds. Double-digit growth is being driven by rising demand in areas from smoothies to cereals, trail mixes and snacks.

Even indulgent products, such as chocolate-enrobed dried cranberries are benefiting from the trend. As such growth demonstrates however, health benefits are not the only market driver for cranberries, he points out. "Lots of factors are working in our favour, not least that the availability and price of cranberries are very consistent. The other point is probably an obvious one, but they do taste pretty good!"