Air pockets in roti dough are primarily caused by insufficient gluten development and inadequate resting time, preventing the dough from relaxing and distributing air evenly.
Several factors contribute to the formation of air pockets in roti dough. The most common is insufficient gluten development. Gluten is the protein in wheat flour that provides elasticity and structure to the dough. When the dough isn't kneaded enough, the gluten strands don't develop properly, leading to uneven air distribution.
Another key factor is inadequate resting time. After kneading, the dough needs time to relax. This allows the gluten to relax, making the dough more pliable and easier to roll out evenly. Without sufficient resting, the dough will be tight and prone to trapping air in pockets.
The hydration level of the dough also plays a role. If the dough is too dry, it will be difficult to work with and more likely to form air pockets. Conversely, if the dough is too wet, it can become sticky and also lead to uneven air distribution.
Finally, the rolling technique can also contribute. If you roll the roti unevenly, you can create areas of varying thickness, which can trap air and lead to pockets during cooking.
After kneading, lightly oil the dough ball, cover it with a damp cloth, and let it rest for at least 30 minutes (or even longer) at room temperature. This allows the gluten to relax fully, resulting in softer, more pliable rotis with fewer air pockets.