A. First of all, what exactly IS suet? It is the hard fat around the kidneys and loins of a cow.
Ask for it at the butcher's or at the meat counter of the grocery store and what you'll get is RAW suet, or big chunks of unadulterated cow fat.
Raw suet in this form is solid at temperatures below 70 degrees. Above 70 degrees, raw suet will begin to melt. It can also turn black and go rancid. This is not good for the birds or other wildlife. To store raw suet, it must be refrigerated or frozen.
Suet purchased in cakes, plugs, tubs or some other shape has been RENDERED. Rendering is a process of melting the fat down and putting it through a process of lengthy simmering and straining to remove impurities. (It is a stinky, smelly process...believe me, I did it. Once.)
The end result is a suet that takes longer to go rancid and does not need to be refrigerated. After rendering, it is commonly shaped to easily fit into a product designed specifically to hold suet, such as a cage or a log feeder.
Fun fact: Rendered beef fat is used in some traditional British fare such as Christmas pudding.Fun fact: Suet is added to the food rations of sled dogs to meet their high energy needs.