Saturday, February 21, 2009

A Wrong Turn in Agricultural Production Research?

Consider the difference between the taste of that over-sized strawberry shipped from California and the much smaller strawberries you may grow yourself or remember from childhood. The former, while attractive and perfectly formed, often just does not have the flavor or even the texture found in the latter.

The human sense of taste often leads us astray, e.g., with respect to sugar or salt, but in this instance, we may have it right.

A report published in the February issue of the Journal of Horticultural Science and Biotechnology raises serious questions about “improvements” in fruit and vegetable production adopted by commercial agriculture. Researcher Donald R. Davis compared past studies and the nutritional records of fruits and vegetables produced in the 1930’s with those available in today’s supermarket, and found that today’s vegetables may contain 5% to 40% fewer nutritionally beneficial minerals.

Agricultural research and modern farming practices focus on producing more food at a cheaper cost. Most often this involves producing larger fruits and vegetables in a shorter period of time. Both aspects of production, however, larger size and quicker growth, appear to have an inverse relationship with nutritional value. The larger size is produced through additional “dry matter,” a mostly carbohydrate substance. Rapid growth produces a crop that has had less time to absorb minerals from the soil. And, our selection and manipulation of varieties for the purpose of increasing yield may produce more, but nutritionally inferior products.

In side-by-side plantings, Roberts found:
plantings of low- and high-yield cultivars of broccoli and grains found consistently negative correlations between yield and concentrations of minerals and protein, a newly recognized genetic dilution effect
Blogger discussions of the study abound - see, e.g. U.S. Food Policy, and Kitchen Gardeners International.