Impact of water-extractable components from different cereals on the quality of oat bread

Abstract

Loaf volume and crumb structure of oat bread are not comparable to those of bread from wheat flour. Hydrocolloids, surfactants and/or enzymes are often included in oat batter recipes for quality enhancement reasons. In this study, we examined the impact of water-extractable components from barley, oat, rye and wheat flour on oat bread quality. We speculated that such water extracts contain components which also would enhance the quality of oat bread. As expected, extract protein, non-starch polysaccharide, lipid and enzyme levels varied widely amongst the different cereal flours used. The extracts also varied in foaming properties and extract viscosities. Rye flour contained the highest level of water-extractable components. Inclusion of rye aqueous extract resulted in the largest loaf volume increase and in softer crumb than noted for control oat bread. Rheofermentometer analyses showed that the moment of gas cell opening was delayed when rye extract was added, indicating improved batter gas cell stabilization, while collapse during baking was not affected. The oat bread improving effect of the rye extract is likely due to a combination of the impact of different of its constituents such as enzymes and surface active components.