Suet

Suet is not always easily obtainable, and is not interchangeable.

Suet is a food item derived from the fat of animals such as sheep and cattle, and when fresh it is a white colour.
Suet is typically the hard fat from around the animal’s kidneys, and is unlike other fat found on the animal, so other animal fat alternatives should not be used.
Suet can be an ingredient in pastries and deep-fried dishes, an ingredient in traditional Christmas puddings and others, as well as fruit mince, and it is often found in traditional British recipes of this kind.
Suet is used to create a light and spongy texture in food, due to its higher melting temperature that helps to build structure and creates pockets of air in the partially cooked mixture, and as such, it is best if it is not substituted with any other fat.
If temperatures exceed 45° to 50° Celsius (113° to 122° Fahrenheit), suet beings to melt, a temperature higher than most other fats, and it starts to solidify at temperatures between 37° and 40° Celsius (98.6° and 104° Fahrenheit).

As suet is an animal product, it needs to be stored in the refrigerator, or frozen if long storage times are required, and for cooking purposes, it is usually grated or minced before adding to a recipe.
Suet can be made into bird feed, often in the form of tallow, and has been made into soap, leather cleaners and lamp fuel in the past.
Suet is very high in cholesterol, fat and calories, which has led to its use in the diets of some explorers in history, to contribute to the large energy intake needed in freezing weather conditions.
Among the first mentions of suet as an ingredient, was a recipe of a pudding cooked for the members of Cambridge University in 1617.
Vegetable shortening and frozen butter can be used as a somewhat passable alternative for suet; however the flavour will differ, and the texture is likely to be more dense and oily.

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