Egg yolks and lye calculators

[Silver]

Dear Soap makers!
After having read wonders about including egg yolks into shampoo bar recipes, I was hoping to give it a try. However while trying to come up with my own working recipe, I ran into some trouble with the lye calculators. None of the online lye calculators seem to have egg yolks in the selection lists! How do I calculate my lye for a recipe that has egg yolks?
Many thanks,
Silver

 

[Obsidian]

I counted my yolks as a additive, not a oil. They don't add enough fat to worry about adjusting the lye.

 

[cmzaha]

I suggest tempering your egg yolks with some warm batter or warm soap oils. I sure you probably know this already but though I would mention it.

 

[amd]

Don't forget to remove the yolk membrane before beating up those eggs! (To quote another member... ask me how I know...)

 

[Obsidian]

I push my yolks through a sieve, works great to remove the membrane.

 

[DeeAnna]

An egg yolk weighs about 50 g total with 3.6 g carbohydrates, 26.5 g fat, and 15.9 g protein. 10% of the total weight (5 g) is fatty acids and 9% (4.5 g) is lecithin.

The 5 g of fatty acids in 1 egg yolk is roughly the same blend of fatty acids in 5 g of rice bran oil. So there's not a lot of saponifiable fat in an egg yolk.

Unsaturated fatty acids:
Oleic acid, 47%
Linoleic acid, 16%
Palmitoleic acid, 5%
Linolenic acid, 2%

Saturated fatty acids:
Palmitic acid, 23%
Stearic acid, 4%
Myristic acid, 1%

EDITED TO ADD- DeeAnna has made corrections to some of the above info. See post #8 below to view her updated info. -SMF Modmin Team

 

[Silver]

Ah, that makes sense! Thanks everyone for all the input and suggestions!

 

[DeeAnna]

My previous post #6 contains errors. Here is the correct info:

A large whole egg weighs about 50 g total.

Different sources have slightly different numbers, but "Self Nutrition Data" shows each large whole egg contains under 1 g carbohydrate, about 5 g fat, and about 6 g protein. The rest of the egg's weight is mostly water -- about 37 g.

The egg yolk contains about 5 grams of fat, about one-third of the water, and roughly two-thirds of the protein of the whole egg.

The saponification value of egg fat is similar to the sap value of canola oil. If your soap calculator doesn't include egg fat, enter 5 grams of canola oil for every yolk or whole egg in your recipe.

The fatty acid profile of egg fat is different than canola -- the fatty acid profile is closer to rice bran oil. Since egg fat is such a small % of the total fat in your recipe, however, the fatty acid profile will still be reasonably accurate if you substitute canola for the egg fat.

Each egg white contains essentially no fat, about two-thirds of the water, and roughly one-third of the protein of the whole egg.