The effect of tempering on protein properties and arabinoxylan contents of intermediate wheatgrass (Thinopyrum intermedium) flour

Abstract

Background and objectives To benefit from ecosystem services provided by intermediate wheatgrass (IWG, Thinopyrum intermedium) cultivation, its processing conditions require optimization to facilitate its use in foods. This study assessed tempering as a strategy to improve IWG flour properties relevant for dough making. Findings Tempered IWG samples had significantly higher maximum torque in the GlutoPeak, which strongly correlated with lower contents in total and water‐extractable arabinoxylans (p < .05, r = −0.481; p < .01, r = −0.611) and phosphate buffer‐soluble proteins (p < .01, r = −0.893). While higher maximum torque was observed when IWG was tempered to 14% (compared to 12%), target moisture and tempering time did not have any effect. Tempering induced significant reductions in accessible thiols, which also negatively correlated with maximum torque (p < .05, r = −0.473). SDS‐PAGE analysis, however, did not indicate a shift in flour protein profiles. Conclusions Tempering significantly increased maximum torque and significantly reduced the contents of phosphate buffer‐soluble proteins, accessible thiols, and arabinoxylans. Together, these findings imply increased protein aggregation and an improved IWG protein network. Significance and novelty This work demonstrates that the interaction between proteins and arabinoxylans is crucial for IWG dough properties and can be influenced by processing methods.