What causes air pockets to form in sourdough dough?

Question

Learn what creates air pockets in sourdough and how to control crumb structure.

Answer 1

Air pockets in sourdough dough are primarily caused by the uneven distribution of gas produced during fermentation by wild yeasts and bacteria, often exacerbated by improper shaping or handling.

Detailed Explanation:

Sourdough bread relies on wild yeasts and bacteria, particularly *Lactobacilli*, to ferment the dough. During fermentation, these microorganisms consume sugars in the flour and produce carbon dioxide (CO2) as a byproduct. This CO2 is what creates the air pockets, or alveoli, in the bread. However, several factors can lead to uneven distribution and the formation of large, undesirable air pockets:

1. Uneven Fermentation: If the fermentation process isn't consistent throughout the dough, some areas will produce more gas than others. This can happen if the dough isn't mixed thoroughly or if the temperature isn't uniform.

2. Weak Gluten Structure: A weak gluten network struggles to hold the gas evenly. This can be due to under-mixing, using flour with low protein content, or over-fermentation, which degrades the gluten.

3. Improper Shaping: Shaping the dough incorrectly can trap large pockets of air. If you don't degas the dough gently and create surface tension during shaping, large bubbles can remain.

4. Insufficient Degassing: Failing to gently press out larger air bubbles during the shaping process will result in them remaining in the final loaf.

5. Over-proofing: Over-proofing can lead to a collapse of the gluten structure, resulting in large, irregular air pockets.

Pro Tip:

When shaping your sourdough, gently degas the dough by pressing out large air bubbles with your fingertips. Then, create surface tension by pulling the dough taut and tucking it underneath itself. This helps distribute the gas more evenly and creates a smoother, more consistent crumb.