What specifically causes bread to rise?

Bread rises due to the production of carbon dioxide gas, which is trapped within the dough's gluten structure.

Here's a breakdown of the processes involved:

1. Yeast:

* Yeast, a single-celled fungus, is the primary agent for rising in most bread.

* Yeast consumes sugars (from flour or added sugar) and produces carbon dioxide and alcohol as byproducts.

2. Fermentation:

* Fermentation is the process by which yeast breaks down sugars.

* This process takes time and creates tiny bubbles of carbon dioxide gas within the dough.

3. Gluten:

* Gluten is a protein network formed by the mixing of water and flour.

* Gluten acts like a net, trapping the carbon dioxide bubbles produced by the yeast.

* The gluten network stretches and expands as the bubbles grow, causing the dough to rise.

4. Other factors:

* Temperature: Yeast works best at warm temperatures (70-80°F/21-27°C). Warmer temperatures accelerate fermentation and cause the dough to rise faster.

* Sugar: Sugar provides food for the yeast, which speeds up the fermentation process and makes the dough rise higher.

* Kneading: Kneading develops the gluten network, making it stronger and more capable of holding the carbon dioxide bubbles.

* Proofing: Proofing is the final rise of the dough before baking. During this process, the yeast continues to produce carbon dioxide, allowing the dough to expand to its full potential.

In summary:

* Yeast produces carbon dioxide during fermentation.

* The gluten network traps the carbon dioxide bubbles, causing the dough to rise.

* Temperature, sugar, and kneading all play a role in influencing the rate and extent of rising.