Peppers grown organically contain more vitamin C (ascorbic acid) and higher levels of phenolic compounds, a natural antioxidant, than those cultivated conventionally.
This has been shown by researchers from the Polytechnic University of Valencia (UPV) in a study that focuses on peppers, although their conclusions could be extrapolated to other crops, such as tomatoes and other vegetables.
The results of the study, in which La Unió de Llauradors has collaborated and during which dozens of varieties have been analyzed, have been published in the journal PLoS One, as reported by sources from the university.
What has been shown is that when few inputs are used, "there is a reaction from the tissues, leaves and fruits of plants which allows them to accumulate antioxidants."
This has been explained to EFE by Adrián Rodríguez Burruezo, coordinator of the study and researcher of the Institute for the Improvement and Conservation of the Valencian Agrodiversity (COMAV) of the Polytechnic University of Valencia.
Rodríguez Burruezo says that in the course of the study, they have also observed how "the difference in vitamin C and phenolic compound contents between organic and conventional crops becomes greater as the fruits ripen."
The study is part of the doctoral thesis of Ana María Ribes, PhD student at the COMAV of the UPV, as pointed out by the same sources.
The field work was carried out in a number of experimental plots of the Marjal dels Moros, in Sagunto, Valencia. For two years, the researchers analyzed up to 37 varieties, cultivated both conventionally and organically.
"It is the most comprehensive comparative study that has been carried out to date with peppers from different corners of the world and focused on that organic vs. conventional duality," said Ana María Ribes.
The study has made it possible to learn new details about a number of pepper varieties, including the Valencian, Ibarra, Largo de Reus, Piquillo, Del Bierzo, Riojano, Arnoia or Gernika, among other domestic varieties.
It has also served to learn more about some foreign Designations of Origin, like the Italian Di Senise, and other exotic peppers of great local relevance in America, such as jalapeños, mountain chilies and ají peppers.
María Dolores Raigón, researcher of the COMAV-UPV and co-author of the study, explained that organic farming is based mainly on the application of manure, without the use of pesticides, either synthetic or even those accepted in organic production.
Meanwhile, conventional cultivation is based on the use of synthetic fertilizers and conventional pesticides, said the researcher.
In order to determine the different contributions of nutritional compounds in both types of crops, the researchers resorted to potentiometric and spectrophotometric methods.
"These tools make it possible to evaluate and compare the levels of many nutrients present in large varietal collections (thousands of samples), simply and quickly and with enough precision," said Raigón.
For the researchers of the COMAV of the Polytechnic University of Valencia , the results of this study will add value to the organic production.
"We could even help growers make an on-demand selection of the traditional varieties that will perform the best when grown organically in their specific conditions, both in terms of production and quality," concluded Rodríguez Burruezo.