Egg yolk (raw)
Said to make the lather richer and thicker, though one maker who tested it with care finds the effect small. Brings fat of its own into the bar. Classic Bells supplier or guide, Anne L. Watson supplier or guide, USDA FoodData Central primary source
Opens the calculator’s starter recipe, 1000 g of oils, with this additive at the dose it fills in, ready to change.
What it is
Raw chicken egg yolk, 17 g for a large one: about half water and a quarter fat in USDA’s figures. Makers say it gives a richer lather; one who tested it with care finds the effect small, and it tints a white soap pastel yellow.
USDA FoodData Central primary source, Classic Bells supplier or guide, Anne L. Watson supplier or guide
How much
- 4 % of the oils filled in (from a published recipe) Faiola, Pure Soapmaking primary source
- 4 % of the oils (from a published recipe) Anne L. Watson supplier or guide
- 17–34 g per pound of oils Classic Bells supplier or guide
The calculator fills in 4 % of the oils: 40 g for the 1000 g of oils in its starter recipe.
When and how
- Usually: at light trace.
- Also used: into the oils.
- Blend it smooth first.
Faiola, Pure Soapmaking primary source, Classic Bells supplier or guide, Anne L. Watson supplier or guide
What it does to the recipe
- 52.31 % is water, taken off the recipe’s water.
- 26.54 % is fat, which stays in the bar as extra superfat.
USDA FoodData Central primary source
Worth knowing
- Caution: Heat curdles egg and can bring out an ammonia or rotten-egg smell: keep the oils and the lye solution below 40 °C, mix the yolk with a little of the recipe’s oil, and strain it in. Faiola, Pure Soapmaking primary source, Classic Bells supplier or guide
- Caution: Use the yolks fresh: raw yolks keep only 2 to 4 days in the fridge. FDA primary source
Spoons and drops
- 1 tsp ≈ 5.06 g
- 1 tbsp ≈ 15.2 g
- 1 cup ≈ 243 g
USDA FoodData Central primary source
INCI name
CosIng has no single INCI name for it: label it by what it contains.
Recipes that use it
Guides that discuss it
Sources
Classic Bells (DeeAnna), "Egg Soap": "I suggest 1 whole egg or 1-2 egg yolks or 1 egg white per pound (or per 500 grams) of fats"; a large yolk, "17 g total, supplies 5 g fat, 9 g of water, and 3 g protein"; "Egg yolk supposedly adds richness or thickness to the lather ... although in my experience the effect is small"; "Curdling, odors, and discoloration can happen when these chemicals are heated or become alkaline"; all ingredients "room temperature to lukewarm (below 105 F or 40 C)", the blended egg poured into the fats "through a strainer"; after the lye goes in "there may be an ammonia or “rotten eggs” odor for a short time"; "yolks or whole eggs will tint white soap to a pastel yellow".
Anne L. Watson, Creative Soapmaking, April: Egg Yolk Soap, "2 egg yolks" blended into the liquid fats for 30 oz (850 g) of oils, before the lye; yolks "produce a rich, thick lather"; on scrub soaps, "Some additives, such as minced citrus peel, may become considerably harder and scratchier as the soap ages." At 17 g a large yolk, 34 g for 850 g of oils: 4.0 %.
USDA FoodData Central, food 172184: Egg, yolk, raw, fresh (water 52.31 g, fat 26.54 g, sugars 0.56 g per 100 g; 1 large = 17 g; 1 cup = 243 g).
Anne-Marie Faiola, Pure Soapmaking (Storey Publishing, 2016), chapter 9, Egg Yolk Secret-Feather Swirl: "4 egg yolks, room temperature" combined with "4 ounces olive oil pure" held back from the recipe’s 60 oz of oils; "Temperatures are important in this recipe; you don’t want to “cook” the egg in the oil"; oils and lye-water at 85–95 °F (29–35 °C); at very thin trace, "Pour the egg yolk and oil mixture into the bowl through a strainer. Combine with a whisk." At 17 g a large yolk (USDA FoodData Central 172184), 68 g for 1701 g of oils: 4.0 %.
US Food and Drug Administration, Refrigerator & Freezer Storage Chart: eggs, "Raw yolks, whites", 2–4 days in the refrigerator.