X-rays Could Improve Grain

Pioneering research combining plant breeding and high-intensity synchrotron x-rays is being used to explore the possibility of creating a more mineral-rich, healthier flour.

Scientists from Rothamsted Research, an institute of the UK government funded Biotechnology and Biological Sciences Research Council (BBSRC), are using high-power x-rays from the Diamond Light Source – a third-generation synchrotron in Oxfordshire – to carry out fluorescence analysis to identify new wheat varieties with added health benefits. This rapid approach not only locates several different minerals simultaneously but also provides information about their chemistry and digestibility.

X-ray of a cross section of a wheat grain reveals zinc (blue), iron (green) and manganese (red). (Image: Andrew Neal, Diamond Light Source)

"Essentially we are looking for new, healthier grain," said Dr. Andrew Neal, who leads the project. "Diet deficiency is a big global issue; nearly one million people a year die worldwide as a result of iron and zinc deficiency. Milling methods and our preference for white flour products over whole grain means that much of the essential mineral content of wheat grains is lost during milling to produce white flour. We are looking for ways to increase iron and zinc quantities in white flour, ensuring they end up in our diet.”

A wheat grain consists of bran (the outer layer), the germ (or embryo) and white flour (or starchy endosperm). Wheat bran and germ are rich in protein, fiber, oil, vitamins and minerals, but the endosperm has little valuable mineral content, meaning white flour is virtually devoid of minerals.

Using an x-ray beam line, Neal exposes grains to microfocused high-intensity x-rays. As the x-rays encounter different minerals, characteristic fluorescence x-rays are emitted. Scanning across the energy range of fluorescent x-rays shows a great deal about the properties of the grains, including where and how much of each mineral is present, and how each mineral is complexed within the various regions of the grain.

“It is certainly early days for this approach, but already we are showing that we can screen out unsuitable lines early on, preventing breeders wasting investment in them, and we are able to view wheat grains in a whole new way,” Neal said. “I am hopeful this new approach has real promise to aid nutritious grain development and help answer some of the pressing issues regarding providing more nutritious food from limited productive farmland to feed our increasingly growing population.”

“Food security is a huge challenge for the world. We must not forget that it is not enough to secure enough food for people, we must ensure science helps to deliver enough nutritious food. This research has huge potential both in the UK and abroad and could help to develop products that people want to eat, while increasing their mineral content,” said BBSRC Chief Executive Doug Kell.

BBSRC is one of seven research councils that work together as Research Councils UK (RCUK). It is funded from the government's department for Business, Innovation and Skills (BIS).

The research is highlighted in the latest issue of Business, the quarterly magazine of BBSRC.

For more information, visit: www.bbsrc.ac.uk