Espresso Machines

Coffee beans as we know them are actually the seeds of the coffee tree. There are usually two seeds grown within  a cherry like fruit. While on the tree these seeds are coated with a silverskin, this is a vestigal that remains from the fruits development also known as the spermoderm. The seeds silverskin is sheltered by a parchment like skin (its endocarp), this is covered by a slippery like substance (the parenchyma). This is surrounded by a layer of thin pulp known as the mesocarp. These are all covered with an outer skin; the exocarp. These layers must be removed prior to the roasting of the coffee beans however,there is usually some silverskin that remains intact during the roasting of the beans.

This is the origin of the gourmet coffee as we know it.