Take a look at our fat preparation post for how to prepare the fat and suet for rendering. There are multiple methods of rendering fat into tallow including on the stovetop, in a roasting pan in the oven, in a crockpot, and in an electric roasting pan on the counter. There are different pluses and minuses to each method. I actually use a combination of all of these methods, so that I can render more at a time since I tend to do large amounts. The benefit of using the crockpot is that it is the least likely to burn and is the most efficient at getting all of the liquid fat out. The drawback is that it is also the slowest.
After preparing your fat, the first step in the rendering process is weighing out 5 pounds of fat or suet. The suet is easier to work with and has a better end product but you can use either.
There are 2 different methods used, the wet method where you add salt and water to the fat while cooking down, and the dry method where you just add salt. I prefer the dry method. The wet method decreases the chances of it burning but increases the time it takes to render down. For the dry method, add 5 pounds of fat and 1/4 cup of salt into your crockpot. Set it to low and come back to check it in 4-5 hours. I usually stir it about every hour at this point depending on how it looks. Most of mine are done around the 7-10 hour mark. If you do burn the fat, which is much harder to do in the crockpot, it may darken the color and give it a strong odor.
Cooking down the fat and the suet looks a little different. Fat tends to get kind of hard and rubbery before turning into a fried, rind-looking thing. Whereas, suet will melt off its little latticework and have very few chunks left behind. The goal is to get all the little pockets of liquid fat out of your piece whatever type you are using.
Turn off the crockpot and allow it to cool a little but not so much that it begins to solidify. I like to use plastic storage containers as my molds since they fit in the refrigerator well and have lids that allow stacking. They are made of plastic though, so I don’t want to melt them with my tallow being too hot.
After the fat has cooled sufficiently, pour the melted tallow through a strainer into the mold. I like to use a splatter screen as it has very small holes so it stops the pieces from going through it but will still allow the oil to go through. I do have to go slowly since it is wider than my mold and may spill over otherwise.
There tends to be sediment at the very bottom of the pan and I just try to avoid pouring that in at all if possible. You can shake your screen a little to get the oil through but I don’t recommend much more than that as you don’t want to force the bits to go through the screen and get into your tallow.
Place the mold in a cool place and allow it to harden. I like to use the refrigerator as it speeds up the process.
After it has hardened, remove it from the mold by turning it upside down on the counter. If you have difficulty getting it to release, try to flex the bottom or run the bottom of your container under hot water for a few seconds. It should pop right out.
Any sediment or impurities should have sunk down to the bottom of your mold. If there was more meat on your pieces, you may even see a gelatinous protein on the bottom. These can now be scraped off and discarded. I like to use a spoon for this step. I save all the waste from making my tallow and add it to the dog food later. If you don’t have a dog, you can mix it with peanut butter and roll it in birdseed as a treat for the birds.
At this point, all you have to do is cut the tallow into usable chunks and store it in the refrigerator or the freezer. It should be good for at least a year.
I like to do 2 more steps for mine. I like to purify it, which pulls out more of the impurities, and then I like to can it so I am not using up freezer space and it is good for at least 3 years this way. If you want to see how these steps are done, take a look at our posts for them.