What factors contribute to bitterness in coffee?

Bitterness in coffee primarily stems from compounds inherent in the coffee beans as well as the phenomenon of over-extraction during brewing. The green coffee beans contain various chemical compounds such as chlorogenic acids, which can contribute to a bitter flavor profile when they undergo the roasting process. Additionally, over-extraction can occur when coffee is brewed for too long or with too fine a grind, leading to the unintended extraction of bitter compounds from the coffee grounds. This combination of inherent chemical makeup and brewing technique is crucial in understanding why bitterness manifests in coffee.

While other factors, such as the type of coffee bean, roasting time, and water quality, can also influence the overall taste profile, they do not directly correlate to the extent of bitterness in the same way as the compounds present in the beans and the over-extraction process do.