The liquid fat rendered from pork is called lard.
Lard is produced by heating fatty tissue from a pig until the fat separates from water and connective tissue. It may be rendered with water or steam, known as wet rendering, or heated directly in a pan or oven, known as dry rendering. Once cooled, it becomes a soft or semi-solid fat that can be used in cooking and baking.
The finest baking grade is often called leaf lard, made from the fat surrounding the pig’s kidneys and loin. Because it has little pork flavor, leaf lard is prized for producing flaky pie crusts. Fatback, the firm layer beneath the skin, is another important source. Dry-rendered lard generally has a stronger, more caramelized flavor.
Lard was once as common as butter in parts of Europe and North America. It remains useful for frying, pastry, savory dishes, soap, and some industrial applications. It is different from tallow, which comes mainly from cattle or sheep, and from schmaltz, which usually means rendered poultry fat.