Gathering Summary: Rendering Animal Fat for Soap Making with Sheree Tompkins, June 19, 2013

Melting fat, with Cracklings

Melting fat, with Cracklings

by Catherine Haug, June 23, 2013

(photo, right, by C. Haug)

This is just a short synopsis; you can find more detail in the complete, printable pdf file: [a link will be added here when available]. Sheree had two handouts:

See also related photo-essay on The EssentiaList: Rendering Lard in a Crockpot: The Process

From the Gathering Notice about this event:

Sheree discussed equipment and materials needed to render fat, as well as an overview of the process with a dry demonstration. She also discussed how this fat is used in soap making, and the properties they contribute to the soap; this topic brought the most discussion.

While soaps made from vegetable fats and oils are popular right now, animal fats have served humans well for eons, and they are much less expensive than imported vegetable fats, especially if the fat is from wild game from the local area. Additionally, it is an efficient use of what would otherwise be waste from the butchering of animals.

Animal fats have many other uses, especially in cooking, as they generally tolerate high-heat than the fragile polyunsaturated vegetable oils.

Rendered tallow, in jars

Rendered tallow, in jars

Presentation Topics:

(Photo, right, by S. Tompkins)

  • Equipment and materials for rendering animal fat (lard, suet, tallow)
  • Method using a crockpot
  • Sustainability issues regarding fats and oils
  • Properties of animal fats in soapmaking
  • Using coconut oil for lather
  • What is lye; lye calculators
  • How to use milk in soap making
  • Storage of bulk fats before and after rendering
  • Scenting soap: fragrance oils vs essential oils
  • Natural colorants for soaps

Several Q&A:

Q: How long have you been doing this?

A: I started in 1997.

Q: What can you do with the cracklings?

A: Feed to dog, flavor sauces, and other cooking uses

Q: Which fats/oils do you prefer for soap making?

A: Probably lard, because it is more moisturizing. But adding a bit of coconut oil makes more lather. It’s also important to note that animal fats provide more glycerin than vegetable oils. See also Sheree’s handout: The EssentiaList: Characteristics of Oils in Soap.

Q: I add glycerin to my soap; are you saying I don’t need to do that?

A: You don’t need to add glycerin, especially if you use animal fat, because the saponification (reaction of fats with lye) releases glycerin from the original fat.

Q: How much coconut oil do you add for sudsing?

A: For the soap bars I use to make my laundry soap, I use a 50/50 mix of coconut oil and tallow. For regular bar soap, I use 20% coconut oil. Too much is drying on the skin.

Q: How do you use a lye calculator; what is ‘SAP’

A: You plug in the type(s) of fats you want to use, the amounts of each fat, and the SAP constant. The SAP constant is specific for each type of fat (coconut oil, olive oil, lard, tallow, etc.) and is used by the calculator in determining the amount of lye needed for that fat. Some calculators have the SAP constant built-in; for others you need to add it. Sheree provided a handout that provides the SAP constant and The Characteristics of Oils in Soap.

[The SAP constant is a bit hard to understand. Here’s another definition, from (see the link for more detail and examples):

Definition: When looking at oils for soap making, or calculating a recipe for soap, you’ll see a number associated with each oil called the SAP number. The SAP number is short for the saponification number. This is the units (ounces, grams, pounds) of lye needed to completely react with one unit (ounce, gram, pound) of an oil.”]

Post Script: Cost of rendering your own tallow

Sheree did some calculations on the cost of rendering your own tallow:

“I spent an average of .65 cents per pound for the fat, or $19.50 for 30 pounds. I estimate this will make 3 gallons of cleaned, rendered tallow. This works out to about $6.50 per gallon of rendered tallow. The specific gravity of tallow is .890 which means a gallon of tallow weighs 7.43 lbs. So, that means the cost per pound is about .87 cents.”

For more information

Sheree’s Recommended Books and websites:

Other soapmaking references and resources

Related ESP articles & files

2 Responses to “Gathering Summary: Rendering Animal Fat for Soap Making with Sheree Tompkins, June 19, 2013”

  1. Cosmic Fire says:

    I have had a Soap Factory before.(still have most of the things to do it with). Using Lard and Tallow is essential; Lard being more preferred than the Tallow, even though there still needs to be some Tallow (in most recipes).

    For rendering, I like using Water to simmer, because it agitates the Fat Chunks and keeps them mobile, plus the smell means it is disloging the stink to make more available for the Baking Soda. (so you dont have to keep stirring it)

    Palm and Coconut Oil/s which are difficult to get here because of shipping Costs, will make lots better, firmer, longer lasting soaps….. (at least for skin)

    It would be nice to know if there is anything here more readily available that can be used for a substitute. Safflower, Sunflower, etc. I see at the Flathead Dump, there is empty 50 Gal Drums of several Organic Oils, but no one seems to know who the user is….. someone has a Big Kitchen around here

    I would not use Canola for anything, it is very icky and sticky and too gooey….

    For all the effort making Soaps, it is much more cost effective to setup for larger scale operation to do lets say… 5 gal batches, than messing with 5 bars at a time

    50 Gals of Liquid more organic type Laundry, Dish Soap stuff to distribute to the local community, would make it more worth the effort.

  2. Catherine says:

    Palm oil is not really a good choice from a sustainability aspect, because vital tropical forests are being cut down in order to grow palm trees for the oil. Furthermore, we must import this oil (and also coconut oil) because we cannot grow these tropical trees here. Importing uses polluting fossil fuels.

    Far better to use fats available here, which is primarily animal fats. Canola oil is made here from locally grown canola, but as you state, some soapmakers don’t like using it. Also it is a GMO crop.

    Sunflowers can be grown here, but I don’t know if they are a viable large-scale crop.

    A compromise solution is to use animal fat for the majority of fats in the soap recipe, then adding small amounts of the tropical oils for their beneficial aspects..