Better chocolate

Researchers working with confectionary giant Mars are scouring the genome of the tree Theobroma cacao to find ways of enhancing the health benefits of cocoa beans produced by the plant.

Scientists took two years to unlock the genetic code of the tree and now hope to use the information it contains to improve the quality, flavour and nutritional value of the beans, which are used to produce chocolate.

They believe they can boost the levels of compounds known as flavonols in the beans.

Flavonols have been found in recent research to improve blood pressure and have beneficial effects

The researchers also hope to increase other health qualities that have been attributed to chocolate such as increasing brain function and combating diabetes, while also working to make the fat it contains healthier.

Dr Howard-Yara Shapiro, who is global director of plant science and research at Mars Incorporated, said:

The idea is that this is something that will become the norm – healthy fats, high levels of flavonols.

Chocolate will become something quite different in 10-15-20 years and we are on that track now.

Flavonols have been shown to be good for your heart in many trials.

The genome can help us enhance these molecules in cocoa plants.

We believe we can increase the quality of the cocoa fat to make it healthier.

It is not as easy as it sounds but it is one of our key targets.

It is not something we can deliver tomorrow, but maybe in five years we can.

Having the genome will speed up the process because we will be able to locate which genes are responsible for high levels of flavonols and help us select for those plants.

Dr Shapiro, who is also a professor of environmental sciences at the University of California, persuaded Mars to fund the $10 million project to decode the genome, with the help of computer firm IBM, which analysed the data, and the US Department of Agriculture.

In a little over two years they were able to disentangle the 420 million units of DNA that make up the plant and in an unusual move for a private company, rather than patent the genome, they have now published it online making it available for anyone to use for free.

Dr Shapiro and his team are now searching the cocoa tree's 34,997 genes in the attempt to select key traits that will improve the plants and the chocolate that comes from them.

Traditional breeding techniques can take years to produce trees with the traits they want as thousands of plants must be bred together and then breeders have to wait for the offspring to grow into adult trees before they can see if they have the required physical traits.

Mars initially intends to use natural breeding of the cocoa plants rather than genetic engineering to produce new varieties of trees with boosted traits, but armed with the genome, the process will be sped up massively.

Scientists will be able to take DNA samples from the leaves of the offspring while they are saplings to check if they have carried the genes they want.

But Dr Shapiro added it was possible that some researchers could also use the publicly available genome to create new plants using genetic engineering techniques

But insisted that Mars intended to use traditional breeding techniques.

He said: Rather than having to wait until those trees grow up over five years or so to look at the physical traits of the trees, we can instead take the DNA from the sapling once it sprouts and find out what traits it has.

It speeds up that screening process hugely.

We are still going to have to breed millions of trees and evaluate every single one

But we will very carefully and slowly add traits to the plants that will be sent out to the farmers.

These traits will increase the yield of the plants, give them drought resistance and disease resistance while also making the cocoa bean healthier.

There are currently three million tonnes of cocoa produced every year, but the crops are vulnerable to pests and disease, often causing hundreds of millions of pounds worth of damage.

The production of cocoa has also resulted in large swathes of rainforest being destroyed.

Scientific studies on the health benefits of currently available chocolate have provided mixed results and last week the European Food Safety Authority ruled that manufacturers should not be allowed to advertise these health benefits due to the inconsistent evidence.

Flavonols, which are credited with providing most of chocolate's health benefits, are typically found in dark chocolate and are what helps to give it the bitter taste.

Research has shown they can decrease blood pressure and also increase the function of the vascular system.

They have also been linked to increasing blood flow to the brain, and have been suggested as useful for helping treat stroke patients.

There is also some evidence that they can help reduce insulin resistance in diabetics.

Scientists believe that the genome could help them to identify new flavonols that have a less bitter taste and so their levels can be increased in chocolate bars without making them unpalatable.

They also hope it will lead to other discoveries about other nutrients in the cocoa beans that could be boosted.

Dr Baukje De Roos, from the Rowett Institute of Nutrition and Health at the University of Aberdeen who has been studying the effect of chocolate on cardiovascular health, said boosting the flavonol content of chocolate could give people the health benefits without them having to eat large quantities of the sweet, fatty foods which can be harmful.

She said: We only know the actions of a couple of hundred compounds in the cocoa bean but there are thousands there.

The genome is a really good start, but hopefully in the future we might even identify a lot more bioactive compounds from cocoa that could be beneficial to human health.

Telegraph - Richard Gray