Herbs and spices are natural sources of complex flavors and colors. As with other plant-based material, damage to the plant cells begins a series of enzymatic processes that liberate and develop flavors.
Standard culinary techniques of grinding, grating and chopping herbs and spices increase the surface area of the flavorants. This is another manner in which flavor can be developed. The inherent chemical flavor components are exposed to atmospheric oxygen to develop further unique sensory attributes. Grinding, grating and chopping can also have negative impacts, primarily through exposure and subsequent heating. Generally speaking, flavor molecules are usually relatively small and volatile, and any heating may cause their volatalization and/or chemical decomposition.