Nutrition and Food Systems

Sanet Post, Jonathan S Moscatello,
food value- organic: the ongoing debate
December 10, 1996

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"