How does bread rise?
HOW DOES BREAD RISE?
Did you know that ancient Egyptians discovered that Yeast made the bread rise? Yeast is a microorganism (visible only under a microscope) that grows in colonies (many yeast plants grow together) and they do not have Chlorophyll. Chlorophyll is a substance that plants have and use to make their food. Hence, yeast is a fungus.
As yeast colonies grow, they form enzymes called "zymase" and "invertase." These enzymes change the starch in the bread dough into sugar, and the sugar to alcohol, carbon dioxide and energy. This energy-creating process is called "fermentation."
Now let us try an experiment that shows us how yeast helps bakers make yummy, soft bread.
Yeast in action
Materials in the box
1. 2 teaspoons Active Dry Yeast + 1 teaspoon Sugar mixed together
2. Plastic Cup
3. Plastic Bottle
4. Balloon
Materials from home
1. Warm Water
2. Funnel (optional)
SAFETY: Follow Safety Tips and do this experiment with an adult only!
How do I begin?
1. Ask your Mom / Dad’s help and get some really warm tap water in a bowl and keep ready.
2. Make a watery yeast mixture in the plastic cup by mixing the 2 teaspoons of dried yeast + sugar powder provided, with 2 tablespoons of warm water.
3. Pour the yeast mixture into the plastic bottle and stretch the balloon over its neck.
4. Watch what happens next.
What just happened?
As the yeast starts eating the sugar in the mixture, carbon dioxide gas is formed. This produces bubbles in the mixture and you can see the frothy mixture in the bottle. These bubbles pop and the carbon dioxide gas rises up in the bottle and inflates the balloon within 10-15 minutes.
When bakers make bread, they add sugar to the flour and leave the dough outside for a while. The yeast eats the gluten and sugar in the flour and makes carbon dioxide gas. This forms bubbles in the dough and makes the dough rise up and become fluffy. Once the bread is in the oven, the heat makes the bread rise even more at first, and then the oven's heat kills off the yeast, and the carbon dioxide bubbles escape, leaving back tiny holes in the light, soft bread.
Did you know that ancient Egyptians discovered that Yeast made the bread rise? Yeast is a microorganism (visible only under a microscope) that grows in colonies (many yeast plants grow together) and they do not have Chlorophyll. Chlorophyll is a substance that plants have and use to make their food. Hence, yeast is a fungus.
As yeast colonies grow, they form enzymes called "zymase" and "invertase." These enzymes change the starch in the bread dough into sugar, and the sugar to alcohol, carbon dioxide and energy. This energy-creating process is called "fermentation."
Now let us try an experiment that shows us how yeast helps bakers make yummy, soft bread.
Yeast in action
Materials in the box
1. 2 teaspoons Active Dry Yeast + 1 teaspoon Sugar mixed together
2. Plastic Cup
3. Plastic Bottle
4. Balloon
Materials from home
1. Warm Water
2. Funnel (optional)
SAFETY: Follow Safety Tips and do this experiment with an adult only!
How do I begin?
1. Ask your Mom / Dad’s help and get some really warm tap water in a bowl and keep ready.
2. Make a watery yeast mixture in the plastic cup by mixing the 2 teaspoons of dried yeast + sugar powder provided, with 2 tablespoons of warm water.
3. Pour the yeast mixture into the plastic bottle and stretch the balloon over its neck.
4. Watch what happens next.
What just happened?
As the yeast starts eating the sugar in the mixture, carbon dioxide gas is formed. This produces bubbles in the mixture and you can see the frothy mixture in the bottle. These bubbles pop and the carbon dioxide gas rises up in the bottle and inflates the balloon within 10-15 minutes.
When bakers make bread, they add sugar to the flour and leave the dough outside for a while. The yeast eats the gluten and sugar in the flour and makes carbon dioxide gas. This forms bubbles in the dough and makes the dough rise up and become fluffy. Once the bread is in the oven, the heat makes the bread rise even more at first, and then the oven's heat kills off the yeast, and the carbon dioxide bubbles escape, leaving back tiny holes in the light, soft bread.