S. E. Fayle

ABSTRACT Microbial transglutaminase forms nondisulfide covalent crosslinks in proteins and is being used in foods. This enzyme may produce beneficial effects during breadmaking that are comparable to traditional oxidizing improvers, hypothesized to act via formation of disulfide crosslinks. Transglutaminase greatly improved the crumb strength of baked loaves and provides a potential solution to a common consumer complaint. Transglutaminase also reduced the required work input and substantially improved the water absorption of the dough. Each of these effects would lower processing costs for commercial baking

ABSTRACT: Microbial transglutaminase forms nondisulfide covalent crosslinks in proteins and is increasingly being used in foods. We have previously demonstrated beneficial effects of microbial transglutaminase during breadmaking, which are comparable to traditional oxidizing improvers, hypothesized to act via formation of disulfide crosslinks. Transglutaminase substantially improved the lift of puff pastry. It also had a dramatic effect on the volume of yeasted croissants made with both white flour and a blend of wholemeal and white flour. Furthermore, these effects were preserved after the pastry and croissant doughs had undergone frozen storage for periods of up to 90 d. Transglutaminase, therefore, offers a potential solution to the problem of pastry and croissant dough deterioration on frozen storage.

ABSTRACT: Transglutaminase is a crosslinking enzyme that is finding increasing use in foods, yet the molecular changes responsible for its effects are not fully understood. Proteins were extracted from bread and croissant doughs that had been treated with transglutaminase and compared to those from control doughs by size exclusion high performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. Transglutaminase increased the amount of protein extracted in the gliadin fraction in both bread and croissant doughs. In croissant doughs, a corresponding decrease in the protein extracted in the albumin to globulin fraction was seen. In each case, crosslinking of the high molecular weight glutenins was observed. The possible role of each of these changes on the functional properties of baked products is discussed.

The Maillard reaction comprises a complex network of reactions which has proven to be of great importance in both food science and medicine. The majority of methods developed for studying the Maillard reaction in food have focused on model systems containing amino acids and monosaccharides. In this study, a number of electrophoretic techniques, including two-dimensional gel electrophoresis and capillary electrophoresis, are presented. These have been developed specifically for the analysis of the Maillard reaction of food proteins, and are giving important insights into this complex process.