Effect of Nitrogen Treatment on the Physico-Chemical and Functional Properties Intermediate Wheatgrass (Thinopyrum intermedium) Grown in Different Locations

Background and Objectives: Intermediate wheatgrass (IWG), a new perennial crop, is being explored for food applications; however, nitrogen application effects on its properties have not been investigated. This study evaluated the effects of applying 90 kg ha⁻¹ of nitrogen in spring or fall seasons on the properties of IWG grown in Minnesota and Wisconsin, USA. Findings: Nitrogen treatment increased protein and fat content of IWG while reducing total carbohydrates, regardless of location, treatment time, or refinement. Total dietary fiber increased in whole grain samples. Starch hot paste viscosity generally decreased with nitrogen treatment. Farinograph water absorption and dough stability increased with nitrogen fertilization in samples from Wisconsin. IWG kernel size increased with nitrogen application regardless of growing location and timing of treatment. Conclusion: Nitrogen treatment impacts on IWG properties varied based on growing location, time of application, and whether it was refined or not. While protein and fat contents significantly increased, in the spring season, seed weight was more impacted by fall nitrogen application. Nitrogen treatment also results in strong IWG dough. Significance and Novelty: This study is the first to show the effect of nitrogen fertilization and timing on the properties of IWG.