Newly developed low-phytate breeding lines of wheat have been found to produce flour with 25 percent more magnesium than commercial varieties, according to Agricultural Research Service (ARS) scientists. Varying amounts of magnesium, phosphorus, zinc and other minerals occur naturally in wheat kernels.
Not only do the flours made from these new wheat lines have more magnesium in them, but lower levels of phytic acid may increase the magnesium's bioavailablity, or capacity for uptake and use by people and animals. Magnesium deficiency has been linked to development of osteoporosis and Type 2 diabetes, both of which are on the rise in the United States.
ARS plant geneticist Edward J. Souza and colleagues at the University of Idaho Research and Extension Center in AberdeenMary J. Guitteri and Karen M. Petersonselected the low-phytate lines from greenhouse tests. Souza, formerly at the University of Idaho, is now research leader of the ARS Soft Wheat Quality Research Unit at Wooster, OH. Guitteri is now at the Ohio Agricultural Research and Development Center at Wooster.
The researchers evaluated the low-phytate plants in field trials for two years. Since the new wheat lines have a different distribution of essential minerals, with more in the inner germ than in the outer bran, the flour made from them tends to be more nutritional, whether it is refined or whole-wheat.
Although magnesium deficiency is rare in North America, a high phytate content in grains and the loss of the magnesium in grains' outer coat (bran) that's removed during processing reduce the amount available in the diet. Magnesium isn't usually added to refined flours, so breeding wheat varieties that could add magnesium to American diets would be a natural way to reinforce flours.
Four papers by the scientists addressing various aspects of low-phytate grains appear in the November-December 2006 issue of Crop Science, online at:
ARS is the U.S. Department of Agriculture's chief scientific research agency.