Chapter 68 - Toxic compounds in coffee: Polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are formed from the incomplete combustion of organic material at high temperatures and are potentially genotoxic and carcinogenic, with the entire coffee-production chain at risk of contamination from these substances. However, while environmental contamination is certainly present, the main source of contamination for this matrix is the roasting process, and there is a limited number of ways to mitigate the presence of PAHs in the final product without altering its sensory properties. In this chapter, we aim to provide an overview of the chemistry, biological activity, and regulatory aspects of these contaminants. In view of the contribution of this commodity to the daily intake of PAHs by humans, we also focus on the analytical methods for their determination in green coffee, roasted coffee, instant coffee, and coffee brews. In addition, the by-products of the coffee chain (e.g., husks and spent) are also considered in a circular-economy perspective.