Impact of gluten content and baking method on volume and crumb formation in wheat bread, A pre‐study to in‐situ 4D synchrotron‐based X‐ray tomographic analysis of bread during baking

Abstract

The baking industry looks forward to the use of non-conventional heating oven to speed up the baking process, increasing yield while improving product quality with reduced processing cost. Microwave-baking has shown good potential to contribute with several advantages in this context. However, the final quality of bread baked with microwaves does not match the quality of bread baked with convection. Therefore, combination-baking might be a promising heating technique for bread baking to obtain the advantages with microwave heating but still get the same quality as conventionally baked bread. Additionally, gluten content varies between different kinds of wheat but also from year to year due to fluctuation in the weather. Using a low protein flour when baking bread often results in low volume and poor internal crumb structure. Microwaves have however shown possibilities to increase volume in bread; hence incorporation of microwaves in the baking process might enable usage of weak wheat for bread baking. In this project the impact of gluten content and baking technique on volume and crumb of wheat bread is examined. Volume measurements are made with seed dispersal method and crumb structure is analyzed using image analyses. As a final step in the project, buns are analyzed with X-ray microtomography to prepare for a subsequent in-situ 4D synchrotron-based X-ray tomographic analysis Results showed that gluten content to some extent influence the volume of bread since high protein flour seems to result in higher volume regardless of which baking method that is used. However, the total impact seems to be much more complex than just gluten content since when adding gluten to a low protein flour, the volume of the bread did not reach the same volume as the bread with high protein flour, although the protein content was the same. Further, baking with microwaves seems to encourage the formation of larger pores in bread regardless of which flour that is used.