The gas that bubbles in the dough to make it rise is carbon dioxide. This gas is produced during fermentation by yeast or chemical leavening agents. The carbon dioxide forms bubbles in the dough, causing it to expand and rise.
The yeast consumes the natural sugars in the dough and causes bubbles to form. This causes the dough to rise. It's being blown up by the yeast.
The leavening agent reacts with moisture, heat, acidity, or other triggers to produce gas that becomes trapped as bubbles within the dough. When the dough is baked, it "sets" and the holes left by the gas bubbles remain, giving bread the baked goods their soft, sponge-like textures.
The yeast feeds on the sugar and releases CO2 gas as it does so. The gas bubbles make the dough rise.
No, air by itself does not make bread rise. In yeast dough, the micro organisms (yeast) consume sugars in the dough and produce gas. The gas bubbles are trapped in molecules of protein in the dough called gluten. These gas bubbles expand and cause the dough to rise. When the dough is baked, the heat makes the gas bubbles expand further producing soft delicious bread.
To rise dough effectively for baking, follow these steps: Knead the dough thoroughly to develop gluten. Place the dough in a warm, draft-free area to rise. Cover the dough with a damp cloth or plastic wrap to prevent it from drying out. Allow the dough to rise until it has doubled in size. Punch down the dough to release air bubbles before shaping and baking.
In baking, the purpose of yeast is 'leavening'. That is 'to make the dough rise' by producing gas to make bubbles in the dough. Baking powder and eggs share a similar purpose in recipes. In brewing, it is to introduce bacteria to the brew to aid in fermentation.
To show that yeast was responsible for making the dough rise, you can conduct an experiment where you prepare two batches of dough- one with yeast and one without. Allow both doughs to rise, and observe that the dough with yeast rises significantly more due to the yeast's fermentation process producing gases that make the dough expand.
Oxygen is added to bread dough through the process of kneading. When dough is kneaded, the gluten in the flour is formed into a network that traps air bubbles. These air bubbles help the dough rise during fermentation, leading to a light and airy bread texture.
Put a little of the yeast in a glass of warm water. If you see tiny bubbles, the yeast is still good. If not, adding the dead yeast will not make the dough rise.
Just a touch...depending on how much dough you are making.
Yeast is the type of fungus used to make bread rise. Yeast consumes sugars in the dough and produces carbon dioxide gas, which creates the bubbles that cause the bread to rise and become fluffy.