Green coffee is a durable substance before roasting, with storage needs and properties much like beans or whole grains. Green coffee is considered fresh for six months to a year, at which point flavors begin to change and coffees are described as “past crop”.
Roasting is a transformative and fairly intense process. The green coffee is brought to a temperature of between 410°F and 430°F in fifteen to twenty minutes, then rapidly cooled. For large quantities this requires a purpose-built coffee roaster, but it can also be done in a wok, frying pan or popcorn popper on your kitchen stove.