More than 200 compounds have been isolated from wood smoke. However, not all components are present in al smoked foods; factors such as temperature, humidity and degree of oxidation directly influence which compounds will occur. Major flavoring compounds include aldehydes, ketones, carboxyl acids and phenols.

The aldehydes, ketones and carboxyl acids are derived from the oxidation of the cellulose structure of the wood, while the phenols result when lignin is oxidized. (Lignin is what gives wood its characteristic texture.) The variations in cellulose and lignin content that occur between types of wood accounts for each variety's distinctive flavors.

Wood smoke also contains formaldehyde. This compound is what allows smoke to act as a preservative.