Suet vs Tallow

[BrewerGeorge]

I'm watching a youtube series about 18th century cooking from the excellent Townsends channel from here in Indiana. He's been talking about the difference between suet and tallow in cooking, which of course got me thinking about soap.

Suet is organ fat from around the kidneys and is much harder than muscle fat. According to what I've read, it contains higher levels of stearins than muscle fat. Tallow is a more difficult word as it seems to be used more generically. "Tallow candles" for instance cannot be made with muscle fat because it wouldn't harden, so they should really be called "suet candles" I suppose. Plus modern rendered tallows are likely mixtures of both suet and muscle fats, to further confuse the issue. But it seems that generally the word tallow is used for muscle fat among those making the distinction. Grasslands sells frozen, unrendered suet in 5 lb quantities for $28. that would work out to about $7/lb after rendering, assuming an 80% yield.

So the question is: What's that all mean for soap? Has anyone experimented with the differences? What would we expect the additional stearins to do?

 

[SaltedFig]

George, it works exactly the way you described - tallow (rendered from leftovers of meat production) makes for a softer soap than suet (taken from the leaf fat).

It is noticeable.

Tallow fats soaps can get DOS quicker than suet soaps and have a much stronger "meaty" smell that is detectable in the final soap. Tallow soaps are not as white as suet soaps.

Suet soaps are harder and a lot whiter, have very little smell by comparison and generally last longer.

 

[Moose Wrangler]

Oops, guess I made suet soap last weekend! I generally don't use any animal products in my soap (vegetarian/dairy free here) but we got beef kidney for the dog to eat and I didn't want (a) him eating that much fat and (b) the fat to go to waste.

I can't help with any differences as I previously had zero experience with animal fats in soap but did want to chime in to say thanks for the post, I learned something new.