In situ monitoring of energy-efficient microwave bread baking vs conventional baking using 4D SRCT

Purpose and goal:

One aim was to depen the insights for Swedish baking industry within baking technology with energy-saving potential (based on microwaves), as well as how the choice of ingredients affects the end result. Specifically, this was done by, via improvement of previously developed measurement methods, in an X-ray tomographic environment with high spatial and temporal resolution, measuring how the cell structure of the bread changes over time.

In the long run there is hope that insights from this type of measurement will contribute to innovations and a strengthened Swedish bakery industry. Expected results and effects:

The time evolution of the analysed parameters shows differences between convection baking and combined microwaves-convection baking which can give an understanding of the transfer from dough to bread. In combination baking there is a continuous decrease in the thickness of the cell walls, but in convection the wall thickness increases initially, then decreases, and often increases again.

Noticeable is also the change of cell structure over time vs. choice of recipe. For example the addition of emulsifiers and lipase seems to give different dynamics in the baking process. Approach and implementation:

RISE, Lantmännen and Lund University/Faculty of Engineering (LU/LTH) collaborated in the project. Initial scans of bread at LTH provided insights that could be used at two beam-times at TOMCAT, Paul Scherrer Institute (PSI), Switzerland that were used to make the microtomographic measurements that gave the project its end results. The results also rooted in advanced data analysis.

The measurements were also made possible by the fact that the oven used in the project underwent some necessary modifications regarding how the microwave energy was supplied.