|
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 Zörb, 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. Zörb 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. --Ciara Curtin |
|
|
Part of article from Scientific American
In 1978 the researchers began studying four plots of land planted with winter wheat, potatoes, beets, grass clover
and barley (see image). Farmers cultivated two of these fields conventionally. For the remainder, they utilized organic
methods, substituting compost and manure for synthetic fertilizers and using mechanical weeding and plant extracts instead
of chemical pesticides. The scientists found that organic soils harbored about 50 percent fewer nutrients (because plants
received no artificial fertilizer) but yielded on average only 20 percent less crop. Thus, plants farmed organically used
available nutrients more efficiently. How does this happen? It seems that biodiversity on organic land is far higher than
in traditionally cultivated soils. Moreover, root-colonizing fungi that help plants absorb nutrients, as well as pest-eating
spiders and nutrient-cycling soil microbes, exist in significantly greater numbers on organically tilled plots.
There is much
brew hah-hah about the benefits of organically produced crops. It is like an
article of faith, lacking compelling support upon careful examination. The principle
advantage to organic methods is more humus in the soil. The principle disadvantages
are increased labor, lower yield, greater cost of fertilization, lack of efficiency of scale, and greater insect infestation. These result in a doubling in price to the consumer--jk.
Scientific American
is used as a source of numerous articles by California Skeptics because of its editorial review which is committed to balance
reporting which includes mention of issues which are still being debated. Moreover,
nearly all their in-depth articles are produced by experts in their field. Page
for page they contain more information than those found in the mass media because they devote less space about the researchers
and stick to the essentials about their work. They were once similar to
American Scientist in format, but since being bought in 1986 by the Holtzbrinck group of Germany. It now geared to a less educated readership and thus has significantly less
technical information; and there are more general, informative articles and less on specific areas of research.
It has been continuously
published in the U. S. since 1845, and has a monthly circulation
of over 600,000. There are foreign issues in over a half dozen languages. Scientific American now also produces the PBS program Scientific American Frontiers--jk.
|
