Substitutes for soap

Shea butter substitutes in soap

Shea butter hardens a bar with stearic acid and conditions it with oleic, and in the bar below several fats land close to it. Lard and palm oil come closest on the numbers; among the butters, mango and then cupuaçu. Each takes a little more lye than shea: weigh the lye for shea and put in lard, and the bar comes out at 6.3 % superfat instead of 5 %, more oil left over, which is the safe way round.

The bar they are tried in

Shea butter20 %
Olive oil50 %
Coconut oil25 %
Castor oil5 %

NaOH · 1000 g · Superfat 5 % 138.6 g

The bar: 20 % shea butter, at a 5 % superfat, for 1,000 g of oils. The rest: 50 % olive oil, 25 % coconut oil, and 5 % castor oil. As it is, it needs 138.6 g of sodium hydroxide.

Open the bar in the lye calculator

The substitutes, closest first

Substitute	Sodium hydroxide, g	With the lye left as it was
1Lard	140.6	6.3 %recalculate
2Palm oil	140.8	6.5 %recalculate
3Mango butter	139.8	5.8 %recalculate
4Cupuaçu butter	139.7	5.7 %recalculate
5Tallow	140.4	6.2 %recalculate
6Sal butter	139.2	5.4 %barely moves
7Kokum butter	139.5	5.6 %recalculate
8Cocoa butter	140.0	5.9 %recalculate
9Illipe butter	139.6	5.6 %recalculate
10Nothing in its place: olive oil takes its share	139.6	5.6 %recalculate

With the lye left as it was: the superfat when the sodium hydroxide weighed for the bar as it is goes in with the substitute, planned at 5 %. Each lye figure opens that bar in the lye calculator, which works out the lye for it.

Side by side: Lard vs shea butter Tallow vs shea butter Palm oil vs shea butter Shea butter vs cocoa butter Shea butter vs mango butter

What each does to the bar

	Hardness	Cleansing	Conditioning	Bubbly lather	Creamy lather	Iodine value	INS	Linoleic and linolenic acid, %
As it is, with shea butter	37	17	59	21	25	59	146	8.4
Lard	37	17	59	22	24	61	147	9.1
Palm oil	38	17	58	22	25	59	149	9.3
Mango butter	38	17	57	21	26	58	149	7.8
Cupuaçu butter	37	17	60	22	24	63	143	10.5
Tallow	39	18	57	22	25	58	149	8.2
Sal butter	39	17	56	21	26	56	149	7.5
Kokum butter	40	17	56	22	27	56	150	7.2
Cocoa butter	41	17	56	21	28	56	151	8.0
Illipe butter	41	17	55	21	29	55	151	7.3
Nothing in its place: olive oil takes its share	32	17	65	21	19	66	141	9.7
Usual range	29–54	12–22	44–69	14–46	16–48	41–70	136–165

Closest means the smallest total change across these figures, each counted against the width of its usual range, as the lye calculator’s swap suggestions count it. It is a convention, not a verdict on the bar: a butter that matches on paper can still melt lower, crack or smell, which the note above and the guides cover.

Guides

Substitutes for other oils

Where these numbers come from

Every figure here is worked out from the oil records, each with its sources on its own page: