CONICET | Buscador de Institutos y Recursos Humanos

The unique viscoelastic properties of gluten proteins are the result of their hydration, unfolding, orientation and complex interchange between sulfhydryl (S-H) and disulfide (S-S) bonds. Emulsifiers with different chemical structures can be employed to improve dough performance and bakery products characteristics. The aim of this study was to evaluate the effect of different emulsifiers on gluten dough extensibility and on loaf characteristics. Gluten (41% w/w) and baking powder (5% w/w) were mixed with distilled water and kneaded homogeneously with a glass rod by hand for 1 min. Four emulsifiers were tested: DATEM (diacetyl tartaric esters of monoglyceride), SSL (sodium stearoyl lactylate), Soy lecithin and Tween80. Samples containing 1% w/w emulsifiers was prepared through replacing the same content of gluten powder with the selected emulsifier and mixing well before adding distilled water into the matrix. Rheological dough properties were measured with a Texture Analyzer (TAXT2i Stable Microsystems, UK) using a Kieffer Extensibility Rig. Loaf mechanical properties were tested by performing a compression test with a compression plate probe (P/75); and, after cutting the crust, a texture profile analysis (TPA) of the crumb were carried out with a cylindrical probe (P/36R). The resistance to extension (Rmax) and extensibility (Emax) were lower for those samples containing lecithin (27 ± 2) and HPMC (64 ± 6) in comparison with the control dough (91 ± 11), indicating a poor protein network connectivity in the presence of these emulsifiers. Texture analysis showed that loaf hardness also decreased in the samples containing lecithin as compared with pure gluten. Similar results were obtained for the crumb. We concluded that emulsifiers affect gluten dough and loaf due to the ability of these molecules to interact with gluten proteins in the bulk of the viscoelastic liquid phase and also by modulating the air-water interfase.