Roasting coffee beans unlocks the aroma and flavors inside the raw green coffee beans. The roasting starts a chemical reaction as the beans are rapidly brought to extreme temperatures. When the beans reach the appropriate roast, they are quickly cooled to stop the process. These now Roasted beans smell more like the coffee we know and love. The light roast coffee beans roast from the raw green bean to a golden brown color.
The first crack is a coffee roasting term to describe the audible cracking sound when roasting a coffee bean. This audible cracking sound signals that the bean is approaching edibility. The crack happens because the coffee beans have expanded and the moisture has evaporated and the resulting pressure causes the bean to crack open. There are two cracks during the roasting process, and light to mediums roasts finish between the two cracks. The light roasts, roasted until just after the first crack when they visibly change color and crack.
Light roasted beans reach an internal temperature of 356°F to 401°F. At or around 300-350 degrees, the beans pop or crack while expanding in size. This is known as the first crack. So a light roast is a coffee bean that has been roasted to just before first crack or just beyond first crack.
Light roast coffee beans are a light brown color with a light body,dry surface and no oil on the surface of the bean. The light roasts have a toasted grain-like taste with a pronounced higher acidity. The origin flavors of the bean are retained more in the taste of a light roast compared to a darker roast. The Light roasts flavors are affected by the climate and the soil of the region the bean is from. This origin bean flavor is particularly obvious in Java coffees and Kenyan coffees.
However, as a rule of thumb coffee roasts fall into one of four categories: light, medium, medium-dark and dark. The time spent roasting doesn’t just affect the taste of the coffee it also affects the amount of caffeine, the acidity and the intensity.
Light roasts contain higher amounts caffeine: light roasts keep the most caffeine from the coffee bean roasting process, generally speaking the longer the roast the less remaining caffeine. The darker the roast the less caffeine left the caffeine essentially burns away during the process.
Some more common roasts in the Light Roast category are Light City and Half City, the Cinnamon Roast, which is tricky because it’s roasted to just before first crack. The New England roast is roasted until the first crack and the stopped suddenly.
The Cinnamon Roast is a very light roast level that is immediate at first crack. The Cinnamon Roast has an underdeveloped sweetness and a clear taste of toasted grain. There is an underlying grassy flavor and prominent sharp acidity present.
The New England Roast is a light roast, which is a mottled brown color. The New England Roast highlights the characteristics of the origin bean while also producing a complex acidity.