Chemical characterization, functionality, and baking quality of intermediate wheatgrass (Thinopyrum intermedium)

Intermediate Wheatgrass (IWG) is a perennial crop with environmental benefits such as reduced soil and water erosion, and increased nitrogen fixation. However, farmers will be reluctant to plant this crop without an established market, which relies on the characterization of IWG grains for parameters relevant to food use. The objective of this study was to analyze IWG for the grains’ chemical composition, functionality, and baking properties. Sixteen IWG lines along with one bulk IWG sample and wheat controls were analyzed for proximate composition, dietary fiber, starch composition, and gluten forming proteins, following standard analytical procedures. Starch pasting properties were monitored using a rapid visco analyzer. Dough rheology was assessed using farinograph and Kieffer. Bread baking tests were also performed following AACCI method. Compared to wheat, IWG samples had higher protein, ash, and dietary fiber contents, yet were deficient in high molecular weight glutenins, an important protein component responsible for dough strength and elasticity. The fat content of IWG samples were similar to those of wheat, but total starch content was lower. Amylose/amylopectin ratio, however, was similar to that of wheat. Rheological data showed weaker IWG dough strength compared to that of wheat. These findings suggest that IWG has a superior nutritional profile, but poses challenges for baked products that require dough rising properties. These results can be explained by the lack of gluten network formation and the higher fiber content that competes with protein and starch for water. This data will assist in future breeding efforts for the development of IWG lines suitable for food applications. This project’s success will also advance cereal science industry to provide highly nutritious products to address consumer’s demand.