Influence of partial substitution of wheat flour with sprouted oat flours on physicochemical and textural characteristics of wheat bread

Abstract

There is an issue to be solved in wheat bread processing that the substitution of oat flour enhanced the nutritional value, but deteriorated the texture of wheat bread. To improve the textural attributes of the bread, the inclusion of sprouted oat flour for up to 120 h was investigated in this study. Results indicated that oat β-glucan (OBG) of the bread decreased from 7.86 to 1.88 g/100 g, while total phenols and γ-aminobutyric increased nearly threefold after sprouting for 120 h. The dough stability and rheological properties of wheat with sprouted oat flour were determined to aid the prediction of the textural properties of the final bread products. There was a positive relationship between stability time and viscoelasticity of mixed dough and textural parameters of wheat bread with sprouting oat flour. Compared with wheat bread with unsprouted oat flour, wheat bread with sprouted oat flour was characterized by lower hardness, chewiness, and gumminess, higher cohesiveness, springiness, and resilience. Additionally, the confocal laser scanning microscope illustrated that unsprouted oat flour destroyed the continuity of gluten protein network. Surprisingly, dough with oat flour sprouting for 72 h presented an orderly and dense network structure resulting from the OBG integration. This study suggests that it is promising to develop multigrain bread with more various nutrition and more satisfying textural attributes by an appropriate sprouting process.