Caul fat (aka caul fat netting, fat netting) is a fatty membrane that is found wrapped around internal organs in several animals. It looks like a thin, semi-elastic clear sheet with veins of fat running through it. It is a natural wrapping material used to encase food prior to cooking to hold ingredients on to its surface, keep it from coming apart (for example in a roulade or crepinette), or simply to keep it moist. The fat melts during cooking and the membrane shrinks slightly to adhere to the surface of the food. It is generally unnoticed by diners as part of the finished what to look for.