Quality of Organic, Conventional Winter Wheat

Background and methodology 

The goal of this study was to evaluate the effects of conventional and organic cultivation on the quality of winter wheat and to give preliminary results of an informal organoleptic (sensory) satisfaction test on bread made from the same variety. Winter wheat (Bolero) was cultivated as a part of a five-year stockless arable crop rotation comparing a conventional and an organic management system. The organic wheat received an organic fertilizer at the rate of 30 N units per ha, while the conventional wheat was fertilized at a rate of 160 N units per ha using chemical fertilizers. The following quality analyses were performed on grain samples from both systems: hector-litre weight, 1000-seed weight, protein content, SDS (Sodium Dodecilsulphate Sedimentation), gluten index, total phenols and bread production qualities of the flour such as resistance to stretching, extensibility, and strength also were taken into account. 


Organic wheat showed 50 percent lower yields in grain and straw than conventional wheat, while the seed weight and bulk weights were not affected by cropping systems. Protein content was about 20 percent lower in the organic wheat samples. Bread production qualities were strongly affected by cropping systems: organic wheat showed lower values in terms of strength, which could lead to a less than optimal increase in bread volume. In contrast, the stretching and extensibility values for conventional wheat flour were lower, which tends to indicate softer dough and bread. 

The nitrogen content was slightly, but significantly, higher in conventional flour and bran samples than in organic ones. Phosphorous content was higher in conventional bran but lower in conventional flour. With regard to phenol content, organic bran was 20 percent higher than conventional bran but not at a statistically significant level. A visual inspection showed that organic bread was different in crust thickness, crumb volume and in crumb structure, and panelists found the organic bread was harder and more flavorful than conventional.

Mazzoncini, M., Belloni, P., Risaliti, R., & Antichi, D. (2007). Organic vs conventional winter wheat quality and organoleptic bread test. Proceedings of the 3rd International Congress of the European Integrated Project Quality Low Input Food (QLIF), University of Hohenheim, Germany, March 20-23. Available on-line at: http://orgprints.org/9753/.