Chemistry of Bread
Hopewell Valley Student Podcasting Network
Chemistry Connections
Chemistry of Bread
Episode 12
Welcome to Chemistry Connections, my name is Maggie Maclean and Lilla Antal and I am your host for episode 12 called Chemistry of Bread. Today I/we will be discussing the chemistry involved in the making of bread.
Segment 1: Introduction to Breadmaking
The first bread was made around 12,000 years ago and was created by coarsely crushed grain mixed with water, with the resulting dough probably laid on heated stones and baked by covering it with hot ashes. At the time, we can imagine it was the tastiest bread out there. However, there is such a wide variety of different types of bread now. Whether it’s sourdough, bagels, croissants, whole grain, Irish soda bread, English muffins, biscuits, pumpernickel, banana bread, or pizza dough it is found in all parts of life. Even people intolerant to these ingredients can enjoy a substitute made with gluten-free dough.
- Maggie: My personal favorite is the classic Irish soda bread with gluten-free wheat of course toasted with raspberry jam and butter. This is the bread my parents made me growing up to connect me to my heritage.
- Lilla: You know I like a good whole grain rye bread toasted with eggs and cheese.
- Unison: Comment down below what YOUR favorite bread is, and while you’re down there smash that like button!!!
Getting back on track… By the late nineteenth century, enzymes in the form of malt were being added to flour and dough to control and aid the breadmaking process in emerging commercial bakeries. However, over time this practice was abandoned as new chemical additives and processing aids became available. Let’s pause here and look at some of the chemistry at work.
Segment 2: The Chemistry Behind Breadmaking
Lilla: The yeast in bread contains enzymes that can break down the starch in the flour into sugars. Yeast produces the enzyme maltase to break maltose into glucose molecules that it can ferment once the starch has been broken down into these simple sugars, other enzymes in yeast act upon simple sugars to produce alcohol and carbon dioxide in the bread-making step called fermentation.
Maggie: The enzymes in yeast are natural catalysts. A catalyst is a substance that speeds up a chemical reaction or lowers the temperature or pressure needed to start one, without itself being consumed during the reaction, in bread making the catalysts accelerate the fermentation of bread. Fermentation is the process where the dough produces and retains carbon dioxide in the form of microscopic air pockets. It rises as a result of this. Catalysts break down complex carbohydrates into sugar which yeast can feed off of. With sugars fueling yeast, it releases CO2 which makes bread rise. An you know I like a fluffy bread.
Lilla: When reactions happen, there energy is needed to break the bonds in the reactants, this is called activation energy. If activation energy is high, reactions are slow because only a few particles will have enough energy to collide. In order for a chemical reaction to occur enough particles have the required energy to allow the reaction to proceed. When the activation energy is high there are less particles that have the energy necessary for the reaction.
Maggie: If activation energy is low however, reactions are faster because more particles have enough of the required activation energy. The reaction has more energy, allowing the particles to move faster. This is where catalysts, like enzymes, come in because the enzymes lower the activation energy allowing for the reaction to occur at a faster rate. Which allows for the yeast in the bread, which contains enzymes, to grows resulting in the formation of bread.
Maggie: Now onto carbon dioxide… though it can kill you it helps in making a great treat. Carbon dioxide is released once the bread is heated causing the bread to rise. In bread making the yeast organisms release carbon dioxide, CO2, as they feed off sugars. As the dough is proofed in a warm environment carbon dioxide is formed. This is why the volume of the dough increases. The carbon dioxide expands and moves through the dough of the bread as it is baked in the oven. This results in a loaf of bread with height.
Lilla: Carbon dioxide is a gas. A gas is one of the three fundamental states of matter that is in a gaseous or vaporous state. The rate at which gas particles move is determined by the temperature of the environment they are in. As the bread heats up in the oven the carbon dioxide gas starts to move faster. This faster movement of gases in the bread is what causes the bread to rise and maintain a higher volume. As the gas particles speed up they create more collisions with the inside surface of the bubbles in the bread. The CO2 collisions allow the bread to maintain a light and fluffy texture as it forms pockets of gas.
Maggie: Now back to where this whole thing began…we chose to study the chemistry of bread because I have celiac disease. Due to having celiac, I cannot have any products containing wheat, barley, oats, malt, or rye so I cannot eat any bread products. We thought it would be funny to study bread considering I cannot consume it. Now we are going to be doing ASMR and taste tests of our homemade gluten-free bread.
*BREAD ASMR TASTE TEST*
Segment 3: Personal Connections
Now back to where this whole thing began…we chose to study the chemistry of bread because I have celiac disease. Due to having celiac, I cannot have any products containing wheat, barley, oats, malt, or rye so I cannot eat any bread products. We thought it would be funny to study bread considering I cannot consume it. Now we are going to be doing ASMR and taste tests of our homemade gluten-free bread.
Before our traste test lets real quick say a big…thank you for listening to this episode of Chemistry Connections. For more student-run podcasts and digital content, make sure that you visit www.hvspn.com.
Sources:
https://www.energy.gov/science/doe-explainscatalysts
Music Credits
Warm Nights by @LakeyInspired