EMULSIFIERS: EFFECT ON TEXTURE PROPERTIES OF WHEAT DOUGH

GÓMEZ, A. V.; AÑON, M. C.; PUPPO, M. C.

Madrid, España

Congreso; 13er Congreso ICC de Cereales y Pan. Cereales en el siglo XXI: presente y futuro.; 2008

International Association for Cereal Science and Technology

EMULSIFIERS: EFFECT ON TEXTURE PROPERTIES OF WHEAT DOUGH  Gómez, A. V.1; Añón, M. C.1; Puppo, M. C.1,2 1CIDCA - Fac. Ciencias Exactas - UNLP - CONICET, 47 y 116 (1900) La Plata. Argentina.   2Facultad de Ciencias Agrarias y Forestales - UNLP, 60 y 119 (1900) La Plata, Argentina.  e-mail: mca@biol.unlp.edu.ar Keywords: wheat dough, emulsifiers, dough rheology Wheat flour dough is a viscoelastic material with rheological properties between a viscous liquid and an elastic solid (Weipert, 1990). Elasticity and tenacity affects dough machinability and textural characteristics of the final product. Emulsifiers like sodium stearoyl lactylate (SSL) and diacetyl tartaric acid esters of mono and diglycerides (DATEM) are anionic compounds widely used to enhance breadmaking. These additives bound to the hydrophobic regions of gluten proteins promoting aggregation due to neutralization of positive charges. The major functions of these compounds during dough mixing and breadmaking are used to be the reinforcement of gluten network, the increase of force and extensibility of dough and the improvement of loaf volume (Stauffer, 1990). The objective of this work was to study the influence of SSL, DATEM and a blend of both emulsifiers in rheological properties of dough prepared with commercial Argentinean wheat flour. The mix was composed by wheat flour (100 g), NaCl (2 g), SSL, DATEM or a SSL:DATEM 1:1 blend (1% and 5% flour base). Dough deformation resistance was analyzed by alveographic parameters (P, L, W). Dough texture (hardness, consistency, adhesiveness and cohesiveness) and relaxation (elasticity, relaxation time) were studied by a modified TPA method, at low deformation level (20%) in a TA-XT2i Texture Analyzer (UK). Emulsifiers did not modify, in any level, the tenacity (P) of the control dough. Extensibility (L) of dough prepared with DATEM (1 and 5%) was lower than that observed for dough without additives. Dough prepared with the blend of emulsifiers presented at both levels, values of L similar to that observed only in the presence of SSL. These results suggest that in a 1:1 mix, the SSL governs the extensibility of dough. On the other hand, the work (W) performed to dough during alveographic extension was not significantly modified with the incorporation of pure and blended emulsifiers at both levels. The incorporation of 1% of DATEM or blend caused a significantly decreased in dough consistency and hardness. At 5% of emulsifiers, only SSL produced a significant increase of these parameters. No significant differences in adhesiveness and cohesiveness between emulsifiers were observed. Results suggest that dough texture was mainly influenced by DATEM. Relaxation tests show that dough elasticity was higher with 5% of incorporated additive, mainly with DATEM. A tendency to increase dough relaxation time with the incorporation of emulsifiers, especially DATEM, was observed. The incorporation of a high hydrophobic molecule, DATEM, to wheat flour produced more elastic although less extensible dough and more resistant to the relaxation process. The different effect of each emulsifier over dough extensibility, relaxation and texture, acting over specific gluten network chains, could be attributed to their distinct chemical formula. The distinct interaction between gluten proteins, mediated by the emulsifiers, would lead to dough with specific breadmaking properties. References ·   Stauffer C.L. 1990. Functional Additives for Bakery Foods. Chapter 3. AVI-Van Nostrand Reinhold. NY, USA. ·   Weipert, D. 1990. The benefits of basic rheometry in studying dough rheology. Cereal Chemistry 67:311-317.