Substitutes for soap

Palm oil substitutes in soap

Palm oil gives a bar its hardness and a creamy lather from palmitic acid, and almost any saturated fat can put that back. On the numbers mango butter comes closest in the bar below, but it melts lower than palm oil and Faiola finds it adds little hardness in practice. Tallow is next, and barely moves the lye. For a vegan bar, shea and cocoa butter, half each, come out at 46 for hardness against palm oil’s 45, with 141.8 g of sodium hydroxide instead of 144.1 g.

The bar they are tried in

Palm oil30 %
Olive oil40 %
Coconut oil30 %

NaOH · 1000 g · Superfat 5 % 144.1 g

The bar: 30 % palm oil, at a 5 % superfat, for 1,000 g of oils. The rest: 40 % olive oil and 30 % coconut oil. As it is, it needs 144.1 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
1Mango butter	142.5	3.9 %recalculate
2Tallow	143.4	4.5 %barely moves
3Shea butter and cocoa butter, half each	141.8	3.4 %recalculate
4Shea butter	140.8	2.7 %recalculate
5Lard	143.7	4.7 %barely moves
6Sal butter	141.7	3.4 %recalculate
7Kokum butter	142.1	3.6 %recalculate
8Cocoa butter	142.8	4.1 %recalculate
9Nothing in its place: olive oil takes its share	142.2	3.7 %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: Palm oil vs tallow Palm oil vs lard Palm oil vs shea butter Palm oil vs cocoa 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 palm oil	45	21	51	21	25	52	161	8.9
Mango butter	45	20	49	20	25	50	161	6.6
Tallow	46	22	48	22	24	50	161	7.2
Shea butter and cocoa butter, half each	46	20	49	20	26	50	160	7.2
Shea butter	44	20	52	20	24	52	156	7.5
Lard	43	21	52	21	22	54	158	8.5
Sal butter	46	20	47	20	26	48	161	6.2
Kokum butter	48	21	48	21	27	47	163	5.7
Cocoa butter	49	20	47	20	28	48	163	6.9
Nothing in its place: olive oil takes its share	36	20	60	20	15	62	148	9.5
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: