Compositional evaluation of perennial wheatgrass (Thinopyrum intermedium) breeding populations

A shift to perennial grain cultivation offers environmental benefits such as reduced soil erosion and nitrogen leaching. Recently, tremendous agronomic accomplishments have been made in domesticating perennial intermediate wheatgrass (Thinopyrum intermedium, IWG). Thirteen IWG breeding populations were evaluated for characteristics relevant to food use, including chemical composition, activity of enzymes responsible for rancidity, content of antioxidants (carotenoids and hydroxycinnamic acids) and in vitro antioxidant activity based on the 2,2-diphenyl-1-picrylhydrazyl and Folin-Ciocalteu assays. IWG populations had higher insoluble dietary fibre, protein, fat and ash, but less starch than wheat. IWG populations were deficient in high-molecular weight glutenins yet contained appreciable amounts of gliadins. Some populations exhibited significantly lower lipase activity than wheat, and all had lower lipoxygenase activities. Most IWG populations contained higher levels of antioxidants than wheat. This work provided key phenotypic information for developing IWG lines that combine high fibre, protein and antioxidant contents with minimal rancidity development.