Coffee is often categorized to light, medium or dark roast. Paulig coffees have five different roast levels from 1 to 5. During the roasting the beans get their brown color and the flavors in the bean comes alive. Longer the coffee is roasted the larger the beans will be also its weigh will decrease. Therefore, dark roasted coffees are bigger in volume than light roasted coffees.
Light roasted coffees are often more acidic in flavor and on the other hand dark roasted coffees more bitter. Therefore, dark roasted coffees might be easier on stomach. Light roasted coffees are often more versatile, complex and there are many flavors present. Dark roasted coffees are more full-bodied and stronger.
The roast level depends how long and how high temperature coffee is roasted, longer and higher means darker roast. Some might think that light roasted coffees could be made taste stronger and more like dark roasts by portioning more coffee but this will only make coffee bitter and dull.