Caul fat is a lacy membrane of fat, or lard, that surrounds the stomach and other digestive organs of animals such as cows, sheep, and pigs. It's sometimes called fat netting, and in France, it is often referred to as crépine.
Caul fat has a stringy texture (which makes it difficult to render) and a pronounced porky flavor. Its unique construction gives it a unique function as a wrapper for sausages and forcemeats.
Understanding Lard Varieties
There are three varieties of lard that can be obtained from the carcass of a hog, and each has its own particular characteristics and best uses:
- Pork fatback is the fat that comes from underneath the skin on the back and shoulders. When generally referring to lard, fatback is the common variety. Fatback has a distinct porky flavor, and it's great for making sausages—just chop it up and add it to a grinder. Fatback can be rendered and used it for cooking and baking. Pork fatback makes a superbly flaky pastry for pies and other baked goods. Fatback is sometimes called hard fat.
- Leaf lard is a soft fat that's harvested from around the kidneys. Because there's less of it than fatback, and because it's so soft, leaf lard is something of a delicacy. It has a very neutral flavor, and when rendered it is probably the best type of shortening for making pie crusts.
- Caul fat is the lacy membrane encases the digestive organs and is extremely delicate. It is not usually rendered since there is so little of it.
Cooking With Caul Fat
The classical French tradition of charcuterie, or sausage-making, features a number of items that consist of some type of filling wrapped in caul fat. These items are called crépinettes and they can be shaped like patties or small cylindrical bundles.
Cooking crépinettes is usually done on the grill.
During the cooking, the caul fat will melt away, by which time the forcemeat within will be cooked and will continue to hold its shape. The fat also adds moisture and flavor to the forcemeat as it cooks. Crépinettes can also be done in a hot skillet or in the oven.
An entire caul can be used to wrap a large roulade or even an entire roast. When employed this way, it's essentially a form of barding, or wrapping meat in a layer of fat before roasting.
Buying Caul Fat
Finding caul fat can be a challenge. Your best bet is to inquire at a local butcher shop, especially if they do their own fabricating (a fancy word in butcher-ese that means "cutting up"). They might not have any on hand, but if you put in a request, they may be able to save it for you. If you are unable to find caul fat at a local butcher shop, another option is to buy it online from specialty stores and butchers. You can store the frozen caul fat in the freezer until you are ready to use it.