Bread Baking Science Quiz

<p>Nuclear magnetic resonance imaging (MRI) (C)</p> Signup and view all the answers

<p>Uneven pressure distribution (D)</p> Signup and view all the answers

<p>It aids in aroma compound formation. (C)</p> Signup and view all the answers

<p>Air pressure during baking (C)</p> Signup and view all the answers

<p>Collapse of the product (D)</p> Signup and view all the answers

<p>It delays evaporation by condensation. (C)</p> Signup and view all the answers

<p>The rate of increase levels out. (B)</p> Signup and view all the answers

<p>Condensation occurs. (A)</p> Signup and view all the answers

<p>Intact starch granules. (C)</p> Signup and view all the answers

<p>It enhances the formation of glossy crusts. (A)</p> Signup and view all the answers

<p>Low permeability of surface layers. (D)</p> Signup and view all the answers

<p>A dull surface and harsh color. (B)</p> Signup and view all the answers

<p>It limits gas development in the surface layers. (D)</p> Signup and view all the answers

<p>Viscosity of wheat dough as it relates to temperature (C)</p> Signup and view all the answers

<p>Biaxial deformation (D)</p> Signup and view all the answers

<p>60-80°C (A)</p> Signup and view all the answers

<p>44% (C)</p> Signup and view all the answers

<p>Higher temperatures consistently lead to lower viscosity. (B)</p> Signup and view all the answers

<p>Viscosity remains static regardless of temperature in tensile mode. (A)</p> Signup and view all the answers

<p>Lassoued-Qualdi (D)</p> Signup and view all the answers

<p>$10^2$ to $10^4$ Pa.s (D)</p> Signup and view all the answers

<p>11 to 30% (D)</p> Signup and view all the answers

<p>Hydration-facilitated melting (B)</p> Signup and view all the answers

<p>2–12% (C)</p> Signup and view all the answers

<p>1–5% (A)</p> Signup and view all the answers

<p>Increases by 1–3% (D)</p> Signup and view all the answers

<p>Swelling of granules and amylose exudation (D)</p> Signup and view all the answers

<p>32–38% (B)</p> Signup and view all the answers

<p>Increases as soluble amylose concentration rises (B)</p> Signup and view all the answers

<p>To explore the impact of gas influx and outflux on dough structure (B)</p> Signup and view all the answers

<p>Bubbles formation (A)</p> Signup and view all the answers

<p>The porous structure would collapse (A)</p> Signup and view all the answers

<p>Starch gelatinization (B)</p> Signup and view all the answers

<p>MRI scanning (B)</p> Signup and view all the answers

<p>The stability of the gas bubbles (D)</p> Signup and view all the answers

<p>Formation of large bubbles (C)</p> Signup and view all the answers

<p>It initially increases before stabilizing (B)</p> Signup and view all the answers

<p>It stabilizes and maintains its bubble structure (A)</p> Signup and view all the answers

<p>Region 4 (C)</p> Signup and view all the answers

<p>Phase 2 (C)</p> Signup and view all the answers

<p>Finite rate of starch structure changes (B)</p> Signup and view all the answers

<p>Formation of a three-dimensional network (C)</p> Signup and view all the answers

<p>1 to 2 × 10–3 s−1 (A)</p> Signup and view all the answers

<p>75 to 100 °C (C)</p> Signup and view all the answers

<p>Decrease in viscosity at high temperatures (A)</p> Signup and view all the answers

<p>Influence on retrogradation processes (B)</p> Signup and view all the answers

<p>Starch gelatinization and protein coagulation (A)</p> Signup and view all the answers

The property of a material that resists deformation under stress. It measures a substance's resistance to flow.

The process by which a substance undergoes a change in its physical state, typically from a solid to a liquid, due to an increase in temperature.

The point at which a substance transitions from a solid to a liquid state.

A type of deformation where a material is stretched or pulled in one direction.

A type of deformation where a material is compressed or squeezed from multiple sides.

A material's ability to deform or change shape under applied stress, and return to its original shape when the stress is removed.

The ability of a material to permanently deform or change shape under applied stress.

The process by which a material experiences changes in its properties, including its viscosity and elasticity, as its temperature increases.

The increase in pressure within a bread dough during baking, caused by the expansion of gas bubbles (mainly CO2) and the expansion of water vapor.

A process where the internal pressure of bread dough exceeds the strength of the crust, causing it to break and release gas. This can happen during the oven rise.

A sudden decrease in pressure inside bread dough that can occur during baking, often starting around 40°C and continuing up to 70°C. This can happen due to the release of gases like CO2 and water vapor.

The process of water being converted from a liquid to a gas (water vapor) during baking. This contributes to cell expansion and the overall rise of bread.

The process of starch granules absorbing water and swelling during baking, which contributes to the structure and texture of bread.

The uneven distribution of water content across a baked product, which can affect the texture and appearance.

The loss of water from a baked product during and after baking, which can affect the final moisture content and texture.

The collapse of a baked product after it is removed from the oven, often due to insufficient structure or improper handling.

The moisture content of baked goods, particularly biscuits, can decrease significantly during baking, even by more than 100%.

Two primary explanations for moisture loss in biscuits: Gas loss and increased rigidity of the dough matrix, or water loss due to starch gelatinization and amylose exudation.

The part of the baked biscuit directly beneath the crust has a lower moisture content than the dough it came from, usually about 2-12% less.

The center of the biscuit, the crumb, tends to retain its initial moisture level or even gain a little water.

Starch granules swell and release amylose during baking, contributing to increased viscosity and a change in texture.

As the concentration of soluble amylose increases and the temperature is below the melting point, amylose molecules associate more, contributing to increased viscosity.

The process where the ordered structure of starch granules is irreversibly altered during baking, resulting in a change in their properties.

The disruption of starch granules due to hydration and the subsequent partial dispersion of amylose and amylopectin.

The first phase of dough viscosity change in baking, characterized by a decrease in viscosity as the dough heats. This phase is attributed to the lack of significant transformations.

The second phase of dough viscosity change, marked by an almost linear increase in viscosity as the dough heats. This is attributed to starch swelling and protein coagulation, the relative contribution of each is uncertain.

The third phase in dough viscosity change, characterized by a decrease in viscosity as the dough heats. This is due to continued changes in starch structure.

The rate at which the dough is heated significantly impacts its viscosity changes. Faster heating leads to a higher temperature at which the minimum viscosity occurs.

The formation of a three-dimensional network in dough, where swollen starch granules are held together by entangled amylose molecules.

The transformation of dough gel during storage, involving further aggregation and recrystallization of amylose chains, resulting in a more stable structure.

The heating rate during baking and the subsequent cooling rate can influence the speed and extent of amylose recrystallization (retrogradation) in dough.

The process of browning in baked goods is directly related to the loss of water during baking.

Steam injection helps to slow down the evaporation of water from the surface of dough during baking by adding moisture to the oven atmosphere.

During the initial stage of baking, water vapor condenses on the dough surface as long as the surface temperature is below the dew point temperature of the oven atmosphere.

The rate of crust temperature increase slows down as the temperature approaches the dew point, indicating the transition from condensation to evaporation of water.

Baking in a dry atmosphere leads to a less appealing, dull surface and a harsher color due to the limited amount of water condensation on the surface of the bread.

Water condensation during baking facilitates the complete gelatinization of starch at the surface, contributing to a glossy crust.

The permeability of the surface layers of bread to gases is negatively affected by their structure, hindering water migration and contributing to pressure buildup during baking.

High levels of steam injection may be necessary to achieve full starch gelatinization at the surface of bread.

As the internal temperature of biscuit dough rises above the surrounding bath temperature, it releases large amounts of gas, causing bubbles to form on the surface and escape toward the exterior of the bath. This outgassing is crucial for maintaining the dough's porous structure before setting by starch gelatinization.

In the context of biscuit dough, the balance between the rate of gas entering the dough (influx) and the rate of gas leaving (outflux) is important for maintaining the dough's porous structure and preventing it from collapsing before starch gelatinization.

The balance mentioned is vital for assessing how the size of the pores in the dough is impacted during baking.

The study by Mizukoshi et al. (1980) on biscuit dough heated in a paraffin bath demonstrated that the process of gas release (outgassing) is critical for influencing the structure of the baked product.

MRI (Magnetic Resonance Imaging) is a powerful tool employed by researchers like Wagner and others (2008) to monitor and understand the changing porosity of bread during baking.

The changes in local porosity of bread over time during baking can be observed using MRI. This technique reveals specific regions of the bread (Regions 1 through 4) with varying thickness as the bread bakes.

The study by Wagner and others (2008) employed MRI to analyze the variations in thickness and area of different regions (Regions 1 through 4) within the bread during baking.

Region 4 (the outer part of the bread) exhibits larger bubbles and a greater area as the baking process progresses, suggesting a greater degree of expansion in this region.

The variation in thickness observed in different regions of the bread over time is a key indicator of the dynamic changes happening during baking.

The combination of MRI analysis with the observation of gas release in biscuit dough allows for a comprehensive understanding of the complex processes that occur during baking, influencing the structure of the final product.