How to Render Fat For Cooking, Soap-Making, Skin-care Recipes, or Candle-Making

For more than a decade I've been rendering fat into tallow (from cattle) and lard (from pigs) for cooking, soap-making, and occasional skin care recipes.

Over the years I've tried every method, made every mistake, and complicated the process (completely unnecessarily) in every imaginable way. Also a few unimaginable ways. I've certainly made as much mess in the kitchen as it's possible to make while rendering fat.

In this post, I'll share the steps I've finally arrived at that are simple, efficient, and relatively mess free, for producing clean rendered fat with little to no odor, every time. 

In this post I'll be focusing on tallow, but this is the same process I use for lard and it would work for other kinds of fat too.

I'll be referring to tallow for soap making since this is the main use I put it to, but tallow can also be used for cooking, candle making, skin care products, and leather care products, to name the uses I'm aware of. 

What is tallow (or suet, as its called before rendering)? 

Tallow starts out as a special fat called suet, that is found around the kidneys of cattle. It's not the same as the fat in the muscle meats, like you find on your steak.

Sheep, deer, and goats also yield suet, but I'm sticking to cattle because that's what we raise¹ and that's the fat I use for soap making.

When you render suet, it turns into "tallow," a hard, clean smelling fat, creamy white to pale yellow in colour, that keeps well and has a multitude of uses. 

Tallow is very similar to our skin’s natural oils, or sebum -- so much so that in Latin, a translation for "tallow" is "sebum." Tallow soap is gentle and non-irritating, and won't disturb your skin's microbiome.

Where to get suet if you don't raise your own cattle?

In my opinion, the best option is to form a relationship with an ethical, local farmer, butcher, or hunter, and ask to buy kidney fat from them.

Animal fat can be ethically sourced from wild animals or animals raised in regenerative ways that have lived satisfying, healthy lives, or it can come from factory-farmed, grain-fed animals in industrial systems that are detrimental to health at every level. 

By forming a direction in-person relationship with whomever you get your tallow from, as well as getting a better product you're also insisting on a little more wholeness and connection in the world. 

How to choose the best suet 

Ask for "kidney fat," or "suet" -- not just "fat." You don't want general fat trimmings.

Choose suet from grass fed animals if you can. It's firmer, whiter, and less greasy than grain-fed, and will render into a harder tallow which is better for soap making. 

Make sure its fresh. Fresh suet should be pale yellow and feel hard and crumbly to the touch. If it's grayish, slimy, or has a strong odor, it's too old and has started to spoil.

Suet has a thin, crackly membrane interwoven throughout. Don't worry about this -- it will render out (I'll tell you all about that, below). 

Once you have your suet, bring it home and either render or freeze it immediately. It freezes well for many months, but it does not keep well in the fridge. 

Preparing the suet before starting the rendering process

Ask the butcher to chop the suet into chunks, the smaller the better. This isn't essential but it will make life easier for you and speed up the rendering process. The butcher may increase the price if you ask for it to be finely chopped (I would, if it were me). 

But, avoid pre-ground suet. Pre-ground is convenient, but it's likely to go rancid faster. 

If the butcher didn't want to chop the suet finely or you didn't want to pay for that extra step, you'll have large, unwieldy chunks of hard fat. Not fun to chop yourself.

You'll have three options: 

1. chop it yourself before starting the rendering process, 
2. rope someone else into chopping it,
3. chop it just enough that the chunks will go into the rendering container and then deal with them once they've softened (more on this below).

Option 1 is my least favorite. Option 2 works really well (the first few times, until your chopping person gets tired of it). Option 3 is probably the best one, all things considered. 

How to render suet (which turns it into tallow)

The quality and shelf life of your tallow and whatever you end up making with it depends on thorough rendering, so its worth doing this step well.

Take heart -- it's not complicated and it's not even particularly time consuming, once you know the process well. 

I use a "wet-rendering" method, because that's what works for me to produce clean tallow with little or no odor.

In short, wet-rendering means putting the fat into a slow cooker or a pot on the stove top with water and salt, melting it, then chilling it.

The salt helps draw out impurities and neutralize odors in the fat. The melted fat rises to the surface; the salty water and the impurities sink to the bottom. Once chilled, separating them is very simple. 

If you're just planning on cooking with your tallow, this is all that's required. If you want to make anything with it you'll need to repeat the process 2 or three times. 

Here's the step by step, with pics... 

Step by step, in pictures 

Step 1 - roughly chopped fat goes into a cooking container with hot water and salt.

Quantities aren't important here. My approach is to pack the slow cooker with as much fat as it will hold with the lid on, sprinkle on a hand full of salt, and pour in up to half a liter of water.

But I know when you're starting out its comforting to have measurements to follow, so here's a starting point: for approximately 1.5 to 2 kg of fat, use up to a liter of water and approximately 1/4 cup of salt. 

The water can be hot if you like, which speeds things up ever so slightly. It's ok if the fat goes in frozen -- which of course slows things down quite a bit. 

In this pic, the fat has started to soften and is now swimming in a mixture of melted fat and hot salty water. It took a few hours (I didn't count) from frozen to this point.

If my timing is bad and my bedtime comes before the fat is rendered, I just turn it off and go to bed. This (below) is what it looks like the next morning. Just turn the slower cooker on again and go about your day, until...

... the chunks of fat are soft enough for my favorite part. The stick blender! This will save you HOURS of slow cooker/stove top time. (Ask me how I know.)

If your chunks of fat went into the pot way too big for the stick blender to handle, you can cut them smaller once they're soft enough, with scissors.  (In my opinion this is preferable to chopping the cold fat beforehand.)

This (below) is what it looks like after blending with the stick blender. The tweezers are for removing the bits of connective tissue that get tangled around the blades of the stick blender, which you can see lying on the plate. (A small pair of needle nosed pliers works better than tweezers, but I have a 13 year old son and you cant have one of those AND a pair of pliers.) 

Keep it barely simmering and stir when you think of it, until you can see clear fat with little bits of fat in it. Then, keep it going until those little bits are fully melted.

When you can see translucent fat with bits of material other than fat in it -- all the little white bits have melted, you're ready to chill it. Pour it into a bowl -- I like glass so I can see what's in there. Straining it is unnecessarily messy and time consuming -- just pour the whole lot in, let it sit on the counter top till its cooled enough to put in the fridge, then chill overnight. 

(WARNING: If you pour hot fat into glass, place the glass bowl or jar in the sink so that if the unthinkable happens and it breaks, you won't have hot fat all over your counter top, floor, and possibly down your legs. Ask me how I know about THAT one.)

This is what it will look like when you get it out... 

And this is what you'll find at the bottom... 

It's very easy to scrape off (and it makes excellent chicken food)...

... then you can put it back in a regular pot on the stove top to melt again and repeat the process. 

Way less sludge this time around...

After scraping the bottom of the fat you can rinse it under cold running water, then decide if its done or if you want to render it a third time.

And that's it. Your options now are to store it or use it. If I wanted to make soap immediately I would cut this block of fat up, weigh out what I need, and get started. 

If you want to store it in glass, you can remelt it one last time then pour it into your jars. (I repeat: put the glass jars in the sink before pouring into them.)

For freezer storage I find that plastic is better than glass. (Plastic stacks better and glass tends to crack when the fat expands.) But I don't like pouring hot fat into plastic containers, lest my soap end up with a credit card worth of fat in it. So at this stage I cut the fat into chunks, let it soften at room temp, then pack the chunks into plastic storage containers and press them down.

It will keep for many many months, probably years, in the freezer, a few months in the fridge, and in a cool climate probably at least a month on the counter top.