Learn why sealed besan packets can puff up. Discover how moisture and gas-producing microbes can cause this, indicating potential spoilage.
1 Answer
Besan packets puff up in humid weather because besan (gram flour) is hygroscopic, meaning it readily absorbs moisture from the air. This absorbed moisture increases the air pressure inside the packet, causing it to inflate.
Detailed Explanation:
Besan, or gram flour, is made from ground chickpeas. It's naturally hygroscopic, which means it has a strong affinity for water and readily absorbs moisture from its surroundings. In humid weather, the air contains a higher concentration of water vapor. When a sealed packet of besan is exposed to this humid air, the besan particles inside absorb the moisture.
This absorption process increases the amount of water vapor inside the sealed packet. As the amount of water vapor increases, so does the air pressure within the packet. Since the packet is sealed, the increased pressure has nowhere to escape, causing the packet to inflate or puff up. The extent of the puffing depends on the humidity level and the permeability of the packaging material. Some packets are more airtight than others, which can affect how much they puff up.
Pro Tip:
To prevent besan from clumping and puffing up, store it in an airtight container in a cool, dry place. Adding a bay leaf to the container can also help absorb excess moisture.