Why does this duo work so well? This marriage is not a coincidence. Onions naturally contain aromatic compounds that are gradually released when cooked. It provides a round and slightly sweet base. Cloves, on the other hand, are rich in eugenol, the molecule responsible for their intense and spicy fragrance. Very concentrated, he could quickly become dominant. Inserted into the onion, it diffuses more gently. The result: a controlled balance, neither too strong nor too discreet. A natural air freshener for the home What is less well known is that this trick goes beyond the culinary context. In the past, in some country homes, an onion with cloves was placed in the kitchen or pantry to reduce lingering odours.