The effectiveness of this pairing is rooted in chemistry. Onions contain natural sugars and aromatic compounds that soften and sweeten as they cook. They create a balanced base.
Cloves, by contrast, are rich in eugenol, a powerful compound responsible for their intense, spicy aroma. Used directly, cloves can easily overpower a dish. Anchored inside an onion, however, their strength is moderated. The diffusion becomes slower and more controlled.
The result is harmony rather than dominance. The warmth of the clove enhances the onion’s sweetness instead of competing with it.
More than a culinary trick
Beyond the kitchen, this simple preparation has also been used in traditional households for practical purposes.
In earlier times, a clove studded onion was sometimes placed in kitchens or pantries to help reduce lingering cooking smells. The onion can absorb certain odours from the air, while the cloves release a warm, spicy fragrance. It is not a substitute for proper ventilation, but it offers a gentle, natural alternative to synthetic air fresheners.