KEY POINTS:
Our mothers and grandmothers told us an apple a day keeps the doctor away - but such an imprecise prescription doesn't really cut it with consumers of the 21st century.
What variety of apple? Peeled or whole? And what sort of doctor?
Scientists at HortResearch are on a mission to answer such questions, and so move fruit up the value chain so that consumers start seeing it as a source not only of nutrition, but of specific health benefits.
Feeling gloomy? Instead of reaching for Prozac, tomorrow's health-conscious consumers might slug down a bottle of juice from a fruit proven to contain serotonin-enhancing compounds.
Prone to stomach upsets? The answer may lie in fruits high in in anti-bacterial and anti-inflammatory properties.
By figuring out which fruit compounds can relieve or prevent certain ailments, HortResearch scientists are hoping to tap into the $30 billion global market for functional foods - and boost the earnings of our $1.3 billion fruit-exporting sector.
HortResearch food business leader Karl Crawford said there were well-established precedents for creating "superfruits", the best known of which was the cranberry. When Harvard University researchers showed that the humble cranberry - traditionally made into a sauce and eaten by Americans with their Thanksgiving turkey - helped prevent urinary tract infections, the market for the fruit was transformed.
Dominated by US company Ocean Spray, trade in cranberry products has increased 150 per cent in the past decade.
Blueberries, pomegranates and the Brazilian acia berry (all claimed to be high in anti-oxidants) are latter-day additions to the superfruit industry.
In its search for New Zealand superfruits, HortResearch is focusing on three broad health areas: mental state and performance (things like sleep, mood, motivation, memory and cognitive decline), physical performance and fitness (including tissue growth, hydration and strength) and gut health and immunity (including ailments such as irritable bowel syndrome and inflammatory bowel diseases).
While gut health is a well-established area for functional food products world-wide, Crawford said the idea that fruit compounds might influence mental performance was new. But with the World Health Organisation predicting that depression will be the second biggest cause of death and disability by 2020, "we know its a very strong coming area".
New Zealand scientists are working on "Project Zen", hunting out "mood foods" - fruits containing compounds with a calming influence. Crawford won't say what they have discovered so far, or which fruits hold the most promise, but gold kiwifruit, blackcurrants, feijoas, tamarillos and boysenberries have all been tested.
"We're interested in creating a mood food product - a beverage or a bar or a shot - although we haven't decided what the format of the product will be yet."
In the area of gut health, Crawford said it was known that fruit could act in a variety of ways.
"The fibre in fruit acts as a pre-biotic so it encourages beneficial bacterial growth. We know that we can influence whether pro-biotic bacteria binds to the gut wall, which is part of having good bacteria colonise your gut. We know that fruit can influence or diminish pathogenic bacteria binding to your gut wall. We know it can influence your immune function and your inflammatory state."
A consortium involving HortResearch, Crop and Food Research, AgResearch and the University of Auckland is studying the influence foods have on the genes associated with Crohn's disease, an inflammatory bowel disorder.
Although HortResearch's main claim to fame is as a breeder of new plant varieties (including the Jazz apple and Zespri Gold kiwifruit), its research into superfruits is as much about uncovering the hidden qualities of fruits already under our noses as it is about breeding new ones.
But in some cases the drive for novel varieties that will tickle the consumer's fancy coincides with the search for fruits with health-giving properties.
A red-fleshed apple being developed at HortResearch - created by crossing a pink apple found in Kazakhstan with New Zealand's high-performance white-fleshed apples - not only looks striking, it carries high quantities of the antioxidant, anthocyanin.
Unfortunately, it doesn't taste too good, so there's still work to be done before it can be brought to market as a superfruit - a process that's likely to take another five years.
Crawford said HortResearch hoped that by next year it would have its first superfruit product. He wouldn't say what it was likely to be, but there's a good chance it will be a fruit we already know well - what will be new will be a set of validated claims about its health effects.
"The interesting thing about functional foods is they can grow overnight by millions of dollars by somebody discovering that something is good for you.
"If we were to discover, for instance, that feijoa is a superfruit, then overnight it could become a multi-million-dollar business for New Zealand," Crawford said.
"A good example is the pomegranate, which until three years ago was sold as a Christmas table decoration in the US.
"Then it was discovered that when juiced it had heart benefits. One product alone, PomWonderful, turns over US$60 million [$84.8 million] a year."
