Physical properties of fresh and frozen stored, microwave-reheated breads, containing hydrocolloids

The physical properties of fresh breads prepared with two flour types and containing guar or xanthan gum at “low” and “high” concentration (0.16 and 0.65 g/100 g flour, respectively) were compared with those of samples that had undergone frozen storage and subsequent thawing by microwave heating. Frozen storage had a major influence on bread properties. A significant shrinkage was observed after thawing a porosity reduction in all samples, a major softening of the crust in control samples and a viscous crumb in most samples. Hydrocolloid type and concentration influence the final properties of the bread to a different extent. Guar gum resulted generally in less desirable, final bread quality, while xanthan addition gave better bread properties at “low” concentration. Differences in respect to the flour type used were mainly observed in the porosity and secondarily in the failure deformation values after microwave heating.