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food value- organic: the ongoing debate



I have a small contribution to the on going discussion concerning 
nutritional attributes of organically grown foods. The work presented 
here is my MS thesis work:
  
 Carrot were grown on adjacent, organically maintained and 
standard culture maintained soils.  The experimental site was the Organic 
Gardening Teaching and Research park, University of Florida, 
Gainesville.  Base soil type is arrendondo deep sand. Standard culture 
soils are managed in a manner similar to many local vegetable farms.  The 
organic 
production area is maintained with additions of composted manure and 
landscape waste at the rate of twenty tons/acre, two times per year.  Soil 
tests showed the organic area higher in most soil mineral cations, 
moisture holding capacity, microbial biomass, and organic matter.  
 Carrot were planted in Feb. 1996 in two adjacent randomized complete 
block experiments. Plots were controlled for the same irrigation, same 
post harvest handeling, stand, population, etc. In the standard culture 
area, 
plots were fertilized with an organic fertilizer (10-10-10) made by 
the Fertrel Corp., of Bainbridge PA. The organic area received the 
same treatments.
  The main independent variable was Carotene content across the two 
differently managed production ares. Also considered was time of 
fertilization. However, no effect was seen across the two production 
areas, residual fertility of the organic soils was most likely the 
cause. The time of application treatments were based on a fertilizer 
rate of 100 lbs N/Acre, divided into three treatments.  All pre-plant, 
50% pre- 50% mid season, 25% pre- 50% mid-season-25% late season.     
 Our results showed significantly different levels of carotene in the 
organic area when compared to the standard culture area.  Organic side 
mean was 650ppm across all treatments, compared to the standard 
culture area 490 ppm.
 This work was a part of a preliminary study into this area of interest. 
This work can be found in the 1996 Proceedings of the Florida State 
Horticultural Society meetings. Later work will include mineral analysis, 
and carotene and mineral tests on weet potato and collard green.
 This work was conducted both for reasons of interest, and because of the 
findings that prior work on the topic of Nutritional attributes of 
organic foods has been mis-quoted. I'm referring to the so called "Firman 
Bear 
Report", which did not actually test organic vs. standard culture but the 
effect of environment on mineral components. I will forward my reference 
to the newsgroup with the subject:
"Quality of Organic Food"