Roasting loss, noun (also known as scorching): It describes the loss in weight from green to roasted beans due to water vapor and roasting gases. In filter coffee it is approximately 15-18%, in espresso it’s approximately 18-24% (due to the longer roasting). In industrial roasting (hot air roasting) the hot beans are cooled with water spray and thus reabsorb moisture, which isn’t exactly beneficial for the taste. (see: roasting)
