Coffee grounds absorption.

Dry, used coffee grounds act as a natural odor absorber thanks to their porous structure and nitrogen content, which binds to and eliminates sulfur-based smell compounds. They leave behind a mild coffee aroma as a side effect.

Method

Spread a thin layer of completely dry used coffee grounds in a bowl and place it inside the microwave overnight with the door closed. Discard the grounds in the morning and wipe the interior with a damp cloth.

Effectiveness

Particularly useful against strong, lingering odors that other methods have not fully removed. The residual coffee scent is pleasant to most people but should be considered if flavor transfer is a concern.