Influences of HMW-GS composition and rye translocations on dough mixing properties and cookie baking quality of soft winter wheat

The sugar-snap cookie baking test is the most commonly performed baking test in the evaluation of soft wheat end-use quality. Soft wheat varieties with good cookie baking potential are believed to be suitable for many other soft wheat products. The significance of high-molecular-weight glutenin subunits (HMW-GSs) and rye translocations, and their associations with gluten strength, are well understood for hard wheat in making bread, but remain poorly understood for soft wheat in making cookies. The influences of HMW-GSs and rye translocations on dough mixing properties and cookie-baking quality of soft wheat were investigated using fifty eastern soft winter (ESW) wheat varieties possessing fourteen predominant HMW-GS profiles. Glu-A1 and Glu-B1 loci significantly influenced dough mixing properties only, whereas the Glu-D1 locus significantly influenced both dough mixing properties and cookie-baking quality. The subunits 1, 7*+8 and 5+10 at the Glu-A1, Glu-B1 and Glu-D1 loci, respectively, were associated with long midline peak time, while only the subunits 2+121 at the Glu-D1 locus exhibited significant associations with improved cookie-baking quality of ESW wheat. The contributions of rye translocations to dough mixing properties and cookie-baking quality depended on HMW-GS profiles. Three HMW-GS profiles (2*, 7+9, 2+121), (2*, 7+8, 2+121) and (1, 7+8, 2+121) were identified to be desirable for making large-diameter cookies as determined by a cluster analysis based on cookie diameter. These results support that soft wheat breeders could make an initial selection of soft wheat breeding lines and varieties possessing desirable cookie-baking potentials by just determination of the subunits 2+121 presence.