What imparts fragrance to flowers, fruits and spices?

The fragrance in flowers, fruits and spices is due to the evaporation of certain volatile chemicals into the air. Flowers produce a scent which is a complex mixture of low molecular weight, with volatile compounds such as esters, is emitted into the atmosphere. No two floral scents are exactly the same because of these compounds. Plants pollinated by bees and flies have sweet scents, those pollinated by beetles have strong musty, spicy, or fruity odours.