Interactions between emulsifiers and gluten proteins: effect on dough overrun and mechanical characteristics.

CLARA SIENA; ANA MARÍA RENATA PILOSOF; MARIANA VON STASZEWSKI; CANDELARIA SÍVORI

Buenos Aires

Simposio; Symposium Ben-Gurion-FCEN "Exploring the frontiers of chemistry: challenges for the 21st century?.; 2019

Universidad Ben-Gurion (Israel) y FCEN-UBA

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 overrun and mechanical 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. In order to closely follow expansion and collapse of foams, samples were constituted in 100 mL graduated cylinders and kept in a water bath at 40ºC during the experiment. Foam expansion was recorded during 110 min, obtaining maximum expansion at 30 min. Dough mechanical properties were tested by performing a texture profile analysis (TPA) at 25ºC in a Texture Analyzer (TAXT2i Stable Microsystems) using a compression plate probe (P/75). The overrun for pure gluten was 112% at 30 min. The addition of lecithin and Tween80 improved the foaming capacity since they showed overruns of 143%. Also, gas retention at longer times was higher in these systems. On the contrary, SSL and DATEM presented lower overruns: 93% and 99%, respectively. Texture analysis showed that dough hardness decreased (97-121 N) in those samples containing emulsifiers as compared with pure gluten (157 N). Similar results were obtained for adhesiveness and chewiness. Thus, emulsifiers increased dough softness and volume 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.