What are the methods of mixing a dough?
Dough MixingWhat is dough mixing?Dough mixing is a process in which flour and water are mixed until gluten is developed, a result of the enhanced interaction between dispersed and hydrated gluten-forming proteins. Its quite different from batter mixing due to differences in their respective formulationsspecifically, the proportion between dry and liquid ingredients. The goal is to:
How does it work?Dough mixing can be viewed as a simple reaction in which the reactants transform into a homogeneous and aerated dough:1
The mixed dough consists of continuous (gluten) and discontinuous or dispersed (air cells) phases. Ideally, this mechanical process creates a visco-elastic mass that has optimum dough handling properties and gas retention capacity, essential for product expansion during proofing and oven spring. Dough formulation that fall into the dough mixing concept should meet the following conditions:
RelevanceMixing is a crucial step in all dough systems used for the manufacture of yeast-leavened baked goods. It is critical to obtain the right rheological properties and consistency of the dough for the production process to run smoothly, as well as achieve the desired finished product quality.
Stages of dough mixing
Excessive mechanical energy and shear break-down the relatively stable molecular interactions between gluten-forming proteins such as disulphide bonds (SS). This causes depolymerization of large gluten aggregates.2 In this stage the dough becomes a fluid and viscous mass (with minimum or no elasticity) that has lost most of its water holding capacity. As a consequence, most of the retained water is released and dough becomes excessively sticky. Relationship between mixing stages and dough statusMixing stageDough statusPick upDough not ready (undermixed)Ingredients insufficiently dispersed (mixture is not homogeneous yet).Initial developmentGluten-forming proteins (gliadins and glutenins) gradually become hydrated and start to develop gluten. Kneading and air incorporation initiates.Clean-upGluten is partially developed (too elastic and poorly extensible).Final developmentDough mixed sufficientlyGluten fully developed. Dough has optimum handling properties and gas retention. Air cells are subdivided and re-distributed.LetdownInitial stage of overmixingGluten starting to become weak.BreakdownFinal stage of overmixingGluten too weak. Effects of Undermixing (dough too cold):DoughFinished Product
Effects of Overmixing (dough too warm):DoughFinished Product
ApplicationDifferent mixers can be used in making bread dough. Capacity (pounds of dough per hour), energy consumption, rpm, acquisition costs, level of process control, hygienic design, are some features that high-speed bakers often consider buying dough mixing equipment.
The addition of salt, sugar and fat should be delayed to reduce dough mixing time. This helps gluten proteins hydrate and develop quickly (clean-up stage takes much less time), and provides maximum friction against mixer bowl. Mixing is an intensive mechanical operation that produces heat from friction. This is evidenced by the temperature increase in the mass being transformed into dough. For proper machining during makeup, a final dough temperature should be close to 7682°F (2528°C). To assess if the dough is properly developed, perform the gluten film test. A small portion of dough is stretched between the hands into a thin, smooth, translucent film to test its extensibility and elasticity: References
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