Improvement of dough rheology, bread quality and bread shelf-life by enzymes combination

Abstract

Present work seeks to systematically analyse the individual and synergistic effects of some gluten-crosslinking enzymes (transglutaminase, glucose oxidase and laccase), along with polysaccharide and gluten degrading enzymes (alpha-amylase, xylanase and protease), in breadmaking systems. Except glucose oxidase (GO) and laccase (LAC), enzymes affected significantly to viscoelastic properties of dough. Results confirmed the strengthening effect exerted by transglutaminase (TG). However, alpha-amylase (AMYL), xylanase (XYL) and protease (PROT) promoted a similar decrease in all dynamic moduli analysed, particularly after 180 min of incubation. Addition of XYL to TG containing samples showed to be an interesting alternative to prevent excessive dough strengthening. Bread quality parameters were significantly affected by individual enzyme addition, except when LAC was used. TG diminished loaf specific volume and provided a finer crumb structure. Polysaccharide degrading enzymes and PROT led to better shape, greater specific volume and void fraction of loaves. Significant interactions between TG and all the other enzymes except GO, were proved. According to crumb texture evolution during storage, bread staling increased with TG addition, whilst AMYL, XYL and PROT exhibited a significant antistaling effect.