The lid of a mixer grinder jar typically has a small hole on top for a specific reason - to allow the release of air pressure and prevent the jar from getting locked or difficult to open during usage. This hole serves as a vent or a relief valve.
When you operate a mixer grinder, especially while blending liquids or processing foods that release gas, pressure can build up inside the jar due to the confined space. Without a vent, this pressure can make it hard to open the jar after use, as the air pressure inside resists the opening action.
The hole on the lid allows the air pressure inside the jar to equalize with the atmospheric pressure outside, preventing any potential vacuum formation or excessive pressure buildup. As a result, the lid can be easily opened after using the mixer grinder without struggling to break the seal caused by the pressure.
Additionally, the hole can also act as a pouring spout for liquids or ingredients, making it easier to pour the contents out of the jar without fully removing the lid. This can be useful for tasks that require pouring or transferring the mixture to another container.