What happens to chlorogenic, citric, and malic acids during roasting?

During the roasting process, chlorogenic, citric, and malic acids degrade due to the high temperatures and chemical reactions that occur. This degradation is part of the broader transformation that coffee beans undergo, as the heat causes the acids to break down into simpler compounds. As roasting progresses, the acidity of the coffee changes, affecting its flavor profile. Specifically, chlorogenic acids are known to reduce in concentration, which can influence the perceived bitterness and acidity of the final brewed coffee. Citric and malic acids also diminish as they are broken down, further contributing to the complexity of flavors and aroma in roasted coffee. Thus, the correct understanding is that these acids do not remain constant or increase but rather degrade throughout the roasting process.