Ricotta is a by-product of the Italy's cheese making industry. It is made from the whey that is left after the curds have separated out.
For many years whey posed something of a problem as it was not easy to dispose of. Then it was discovered that if whey was heated, the casein particles in the whey would fuse together to create a new curd. Drain this curd and you have Ricotta.
Ricotta is sold as a fresh white cheese with a granular consistency. In local shops in Italy it is often shaped like an upturned basin with basketwork marks on the outside, but most of it is sold in plastic tubs. The flavor is mild and sweet.
Ricotta with coffee mixed in is a rare and expensive delicacy.