When it comes to nutrition, wheat bread in the organic aisle of the supermarket may be the same as the loaves found in the conventional bread aisle. Although some organic crops have proved more nourishing than their conventional counterparts, wheat--one of the world's biggest cereal crops--shows no difference, according to the results of a new study.
Christian Z¿rb, a biochemist at Germany's Federal Research Center for Nutrition and Food, and his colleagues analyzed wheat, Triticum aestivum L., grown employing two organic and two conventional methods. For fertilizer, the organic approaches used rotted manure or composted manure with other supplements. The two conventional farming methods differed in whether or not farmyard manure was used to supplement chemical fertilizer. The researchers also had a control plot, which received some manure but was otherwise left alone. Moreover, all the fields underwent the same tillage and crop rotations. Z¿rb and his colleagues sampled each of these five experimental plots.
The researchers ground the wheat specimens into fine meal to test if the different growing methods had any effect on the nutritional quality of the grain. Using gas chromatography and mass spectrometry, they isolated and identified 52 of the component chemicals in the samples. Of these nutrients, which included sugars, sugar alcohols, amino acids and organic acids, there was little to no difference in the amount the assorted meals contained. The various farming methods had little impact on the crop's nutritional value, the researchers report in the October 18 issue of the Journal of Agricultural and Food Chemistry.
Overall, studies have delivered mixed results on the question of whether organic crops are as nutritious as conventional crops, but consumers are not necessarily primarily concerned about the nutritional value of the food when they buy organic. "The value of the organic system is the process," says Kathleen Delate, an agronomist at Iowa State University, who was not associated with this study. "People buy it because of the way it is produced," she adds, noting that some people worry about pesticide residue and other chemical impacts. As for nourishment, wheat, apparently, is wheat--no matter how you grow it.