How does the chemical composition of coffee change during roasting?

• A. Beans absorb moisture and swell
• B. Organic compounds break down and new compounds are formed, altering flavors and aromas
• C. Caffeine content increases significantly
• D. The pH level of the beans becomes more acidic

Answer: (B)

During the roasting process, the chemical composition of coffee undergoes significant transformations that are crucial for developing its flavors and aromas. As coffee beans are heated, the high temperatures cause organic compounds within the beans to break down. This breakdown is accompanied by the Maillard reaction, caramelization, and other complex chemical reactions, leading to the formation of new compounds that contribute to the distinct flavors and aromas associated with roasted coffee.

These changes are what allow the roasted coffee to develop its rich, complex profile, moving from the inherent grassy or vegetal notes of raw green beans to the more pronounced flavors such as nutty, fruity, or chocolaty that are characteristic of different roast levels. This transformation is fundamental to the roasting process and is why the correct choice highlights the breakdown of organic compounds and the creation of new ones, culminating in the desired sensory attributes of brewed coffee.