Helge M. Ulmer

Network Formation in Gluten-Free Bread with Application of Transglutaminase

ABSTRACT One of the main problems associated with gluten-free bread is obtaining a good structure. Transglutaminase (TGase), an enzyme that catalyzes acyl-transfer reactions through which proteins can be cross-linked could be a way to improve the structure of gluten-free breads. The objective of this study was to evaluate the impact of TGase at different levels (0, 0.1, 1, and 10 U of TGase/g of protein) on the quality of gluten-free bread. The recipe consisted of white rice flour (relative amount: 35), potato starch (30), corn flour (22.5), xanthan gum (1), and various protein sources (skim milk powder [SMP] [12.5], soya flour, and egg powder). The influence of the various proteins in combination with the different addition levels of TGase on bread quality (% bake loss, specific volume, color, texture, image characteristics, and total moisture) was determined. Confocal laser-scanning microscopy (CLSM) was used to evaluate the influence of TGase on the microstructure of the bread. Baking tests showed that...