New Zealand: Food for thought over blackcurrants
Are blackcurrants edible superstars?
TIM CRONSHAW investigates.
Are blackcurrants edible superstars? Tim Cronshaw investigates. Blackcurrant grower Dave Eder had a mate with Parkinson's disease who could not write his name and shuffled unsteadily on his feet.
After taking blackcurrant-extract pills for 18 months, he could write legibly and walk without a problem. "He's cleared to fly and can travel anywhere in the world," says Eder, a Canterbury grower who will expand his operation to 283 hectares this year and whose family is part owner of Just the Berries.
"He's normal. He can do the things he could do before he got Parkinson's." A miracle cure? Smoke and mirrors or a scientifically explainable discovery that will change the lives of people for ever?
Time will tell, with scientific research yet to authenticate the result. The pills, produced by Just the Berries, are 20 per cent anthocyanin, the anti-oxidant that gives the berry its dark colouring. Just the Berries is spending millions of dollars on blackcurrant research and development and has offices in Tokyo and Los Angeles.
Eder says other Parkinson's sufferers taking the pills are steadily improving. "Scientists are saying `That's impossible', because when a neuron dies, it dies for ever. "What we believe is happening, and there is evidence in rat trials, is that new neurons are being created in the brain akin to a brain cell.
"We are creating new brain cells. That's the only explanation because they are getting better on it." Armed with a file of research, the blackcurrant industry is itching to let consumers know that the super fruit not only tastes good, but can improve human "wellness". In blackcurrants, as in other fruit, there are macronutrients such as sugars and fibre, and micronutrients such as vitamins and minerals and non-nutritive compounds.
These compounds are not part of the food product, but are associated with the health-giving benefits. Mostly, these compounds are antioxidants and most of them are anthocyanins, which give the fruit its red and purple colour. They help to shield the fruit from pests and diseases, and scientists are looking at how their protective qualities can be crossed over to human health.
Research suggests that the currants may play a role in protecting people from inflammation-associated cardiovascular disorders, neurodegeneration and cancer, as well as offering anti-ageing benefits.
Other studies have found that the micronutrient content of dark berries such as blackcurrants includes high levels of vitamin C and folic acid. HortResearch's food and health business leader, Karl Crawford, does not discount the possibility that blackcurrants might one day help people with neurodegeneration diseases.
However, most of the research at present is aimed at human wellness and functional foods, he says. "Most of the work has been done for berry fruit in blueberries by Jim Joseph, of Tufts University in the United States. He has done a lot of work, principally with rats.
He has fed blueberries to aged rats, which has shown improvements in their ability to remember where their food is and co-ordination to see whether their mental faculties are failing. The tie is that the same kinds of ingredients that are in blueberries are in blackcurrants, so berry fruit has this kind of halo. "What happens when you get Alzheimer's is not well understood. One reasonably well-supported theory is that Alzheimer's disease is an oxidated stress in the brain and the cause of the oxidated stress is an amyloid beta plaque (a protein).
"HortResearch has shown that blackcurrants can protect neuronal cells from this particular amyloid. "That is in the lab and not (tested) in people, so we are not saying blackcurrants can prevent Alzheimer's. We are not at that stage, but there are some interesting indications."
The laboratory work was performed at Auckland's Mount Albert Research Centre. Anthocyanin was shown to defend human brain cells against stress and damage associated with neurological decline. Crawford says as scientists learn more about the disease process, they are finding more about the way fruit can impact on its prevention.
"There is a big gap between eating food that is good for you and our knowledge why. We don't believe it is reasonable to expect that food will treat diseases, but it does have a role in keeping you well. "There is room for both views. It's not that fruit won't treat diseases, it's that our (research) focus is on keeping people well."
His HortResearch colleague, foods for health science leader Dr Margot Skinner, agrees that the line is blurred. She has led the development of bioassays (experiments that use living things to test the toxicity of chemicals) in antioxidants, inflammation, immune support, gut health, and mental-health performance and feeding trials to develop new functional foods.
"We are starting to understand how berries can help combat the oxidated stress involved in degenerative diseases and ageing. "Berries have high levels of anthocyanin and these are known to combat oxidated stress," she says.
It is unknown whether eating the currants may prevent skin from wrinkling, but Japanese research is looking at the role of the fruit in improving blood circulation and its relationship with skin ageing, she says. "Certainly, people are starting to talk about beauty within. You can eat something, and that might well improve the appearance of your skin.
"People are starting to talk about that, but the jury is still out." No human trials are scheduled yet on cognitive decline, but one is planned next year to look at cultivars which are best for gut health.
A GlaxoSmithKline (GSK) blackcurrant consultant, Barrie Abernethy, says the company is not prepared to "fly the flag high yet" until science has validated some of the claims. About one-third of New Zealand's crop goes to producing Ribena, the blackcurrant-flavoured-juice brand owned by GSK.
In the meantime, the company is supporting HortResearch to find out more about the potential of blackcurrant, says Abernethy, who oversees crop quality from its 30 contracted growers. "We think solar energy has some part to play in producing a flavour that is a bit unique. We know our varieties are high in antioxidants and other health-related benefits."
Japan is leading the research as a producer of functional foods for a population concerned about stress and feeling well. Food company Meiji Seika has increased blackcurrant ingredients in its confectionary lines and has built up a research centre to uncover more about the fruit's qualities.
The company began to buy New Zealand blackcurrants after finding they were two to three times higher in antioxidants. Blackcurrant-based products are being marketed as aids to improve vision and to make the eyes look more beautiful.
Dark circles around the eyes are being reduced by using polyphenol from blackcurrants to help improve blood circulation. Other research in Japan has shown that taking a blackcurrant extract orally has a beneficial effect on the skin and may reduce sun damage.
There are indications that anthocyanins may halt damage and repair DNA, which could help to reduce natural ageing effects such as the wrinkling of the skin. Benefits such as relieving eye fatigue and assisting glaucoma treatment through better blood flow have also been scientifically linked to blackcurrant compounds.