Organically grown wheat: carotenoid content : health and socio-economic aspects under organic farming system

Sammanfattning: In today’s world, there is more awareness than ever before about the relationship between food consumption and human health. This awareness is especially relevant for cereals, including wheat, which is one of the most important crops in terms of feeding the world. The aim of this study was to evaluate genotypic influence on carotenoid amount in organically grown wheat genotypes. Furthermore, life cycle analyses of organic wheat farming in the scientific literature were reviewed and compared to similar analyses of conventional wheat farming in order to assess socio-economic and environmental sustainability differences between the two systems. A questionnaire was developed and used as a guideline for a literature review on farmers’ opinions about organic wheat farming. The experimental phase was done through analyzing amounts of four carotenoids (e.g. β-carotene, β-cryptoxanthin, lutein and zeaxanthin), in 33 organically grown wheat genotypes by high performance liquid chromatography (HPLC). Carotenoid contents were compared between and within four genotypic wheat groups; landraces, spelt, primitive and old cultivars, as well as between winter and spring wheats. Within this study, no statistically significant differences of total carotenoids amounts were found across the four wheat groups and the two wheat types. Among the 33 genotypes, total carotenoid amounts were significantly higher in Olands 8, Schweiz and Aura, 4.08, 2.49 and 2.47 (mg/kg of DW), respectively, than in all other genotypes. These results were compared with reports on conventional wheat, and no significant differences were found in carotenoid amounts across studies. Our results on carotenoid content can be combined with findings from previous studies that examined other antioxidant compounds in these same genotypes. While, organic wheat production could benefit the environment, e.g. less water contamination and improved soil quality, there are also drawbacks to the organic wheat farming system. For example, it was demonstrated that organic farming system is not more environmentally sustainable than the conventional systems if the organic market is farther than 2000 Km from the farm, which results in equal fossil fuel consumption and global warming potential (GWP) in both systems. In conclusion, given that some genotypes were identified with significantly higher amounts of total carotenoids, it could be of great value to use these genotypes in future breeding programs to increase the nutritional value of wheat. Organic wheat production could be sustainable in several aspects, such as improved soil quality and potentially reduced GWP, but with a holistic view, several factors exist that could limit its sustainability. For example, economical considerations are often a greater concern than environmental impacts for both farmers and consumers. To realize the full potential of organic wheat farming, more research should be done to inspire consumers and wheat farmers towards broader thinking about organic wheat production and consumption with consideration of total nutrient content as well as environmental and economic sustainability.