What is lard?:
Lard is pig fat in both its rendered and unrendered forms. Lard was commonly used in many cuisines as a cooking fat or shortening, or as a spread similar to butter. Its use in contemporary cuisine has diminished because of health concerns posed by its saturated-fat content and its often negative image; however, many contemporary cooks and bakers favor it over other fats for select uses. The culinary qualities of lard vary somewhat depending on the part of the pig from which the fat was taken and how the lard was processed. Lard is still commonly used to manufacture soap.
How is it made?:
Lard can be obtained from any part of the pig as long as there is a high concentration of fatty tissue. The highest grade of lard, known as leaf lard, is obtained from the "flare" fat deposit surrounding the kidneys and inside the loin. Leaf lard has little pork flavor, making it ideal for use in baked goods, where it is treasured for its ability to produce flaky, moist pie crusts. The next highest grade of lard is obtained from fatback, the hard fat between the back skin and flesh of the pig. The lowest grade (for purposes of rendering into lard) is obtained from the soft caul fat surrounding digestive organs, such as small intestines, though caul fat is often used directly as a wrapping for roasting lean meats or in the manufacture of pâtés.
Lard may be rendered by either of two processes, wet rendering or dry rendering. In wet rendering, pig fat is boiled in water or steamed at a high temperature and the lard, which is insoluble in water, is skimmed off of the surface of the mixture, or it is separated in an industrial centrifuge. In dry rendering, the fat is exposed to high heat in a pan or oven without the presence of water (a process similar to frying bacon). The two processes yield somewhat differing products. Wet-rendered lard has a more neutral flavor, a lighter color, and a high smoke point. Dry-rendered lard is somewhat more browned in color and flavor and has relatively lower smoke point.
Industrially-produced lard, including much of the lard sold in supermarkets, is rendered from a mixture of high and low quality fat sources from throughout the pig. It is typically hydrogenated (which produces trans fats as a by-product), and often treated with bleaching and deodorizing agents, emulsifiers, and antioxidants, such as BHT. Such treatment makes lard shelf stable. (Untreated lard must be refrigerated or frozen to prevent rancidity.)
Consumers seeking a higher-quality source of lard typically seek out artisanal producers of rendered lard, or render it themselves from leaf lard or fatback.
A by-product of dry-rendering lard is deep-fried meat, skin and membrane tissue known as cracklings.
For more on lard:
"High on the Hog" by Corby Kummer, New York Times.
"Praise the lard" by Ed Murrieta, The News Tribune.
"Rendering Lard 2.0" by Derrick Schneider, An Obsession With Food (blog).
"Lard", Food Resource, College of Health and Human Sciences, Oregon State University, February 20, 2007. – Bibliography of food science articles on lard.
Vintage lard advertisements (click on a picture for a larger image):