Rights: The University of Waikato Published 9 June 2011 Download

Red-fleshed apples may be healthier than white-fleshed ones. This is because anthocyanins (the plant antioxidants that give apple flesh and skin its colour) are present in large amounts in red-fleshed apples (a several hundred-fold increase in red flesh compared with white flesh). Here, Richard Espley of Plant & Food Research discusses recent research into the health benefits of anthocyanins and describes how anthocyanin concentration in apples is measured in the lab.

Questions to consider
Would the antioxidant content of a new apple variety affect whether you bought it? What about its aesthetic appeal (such as red flesh colour)?

Transcript

Richard Espley (Plant & Food Research)
Anthocyanins are ingested in the human body, but there is a lot of work going on in this at the moment, and people are really not entirely sure about how this happens, but the anthocyanin compounds pass through the stomach and into the gut and they go through the gut wall.

There is a growing body of evidence now that these plant anthocyanins elevate our own antioxidant systems. In the 90s, there was a study that became labelled the French paradox, and it showed that people who ingested anthocyanins, in that case, in the form of red wine, were actually less prone to heart disease than a separate study where they weren't drinking red wine so they weren't ingesting these anthocyanins.

And that is what started this interest in anthocyanins and how they function in our bodies, and now there is a huge increase in the amount of studies being done in mammalian systems, and for example, a recent study showed that the ingestion of anthocyanins could reduce the proliferation of cancers.

How do we measure the amount of anthocyanins present in an apple? We can take a sample, and we can extract the anthocyanins – anthocyanins are actually very easy to extract. Then we can put it on a machine that can check for the exact signature of that compound.

So is it likely that red-fleshed apples will have a greater health benefit than white-fleshed apples? Well, it’s difficult to predict, but what we can show is that these red-fleshed apples have an increase in anthocyanins, and if we think that anthocyanins are likely to be good for us, then that has to be a good thing.

Acknowledgements
Dr David Stevenson
Additional footage from Plant and Food Research
The Plant Journal (2007) 49, 414–427, Red colouration in apple fruit is due to the activity of the MYB transcription factor, MdMYB10. Richard V. Espley, Roger P. Hellens, Jo Putterill, David E. Stevenson, Sumathi Kutty-Amma and Andrew C. Allan.