Maria owns a bakery and bakes many different types of yeast breads. One day she notices that the bread she baked is flat and does not contain the air bubbles that are usually present. Which of the following would be a good explanation for what has happened to her yeast?

Question

The yeast were very active and produced too much energy.
The yeast did not produce the alcohol needed for the bread to rise.
The yeast did not produce the carbon dioxide needed for the bread to rise.
The yeast produced too much carbon dioxide.

Answer 1

The best explanation for the flat bread that does not contain the air bubbles is: The yeast did not produce the carbon dioxide needed for the bread to rise.

Yeast fermentation typically produces carbon dioxide gas, which gets trapped in the dough and causes it to rise. If there is insufficient carbon dioxide production, the dough will remain flat and lack the air bubbles characteristic of properly risen bread.