Colloidal oatmeal
Oats too fine to scratch: you can barely feel them in the bar. Lovely Greens supplier or guide
Opens the calculator’s starter recipe with this additive in it. No source gives a dose to fill in, so enter your own.
What it is
Colloidal oatmeal is sold as colloidal oat flour. The US FDA lists it as a skin-protectant active ingredient in over-the-counter drugs.
The Soap Kitchen supplier or guide, FDA OTC monograph M016 primary source
How much
- up to 5 % of the batch Bramble Berry supplier or guide
- 2.12 tbsp per pound of oils (from a published recipe) Faiola, Pure Soapmaking primary source
- up to 84.4 % of the batch in rinse-off products, the highest reported use: not a recommendation CIR primary source
No dose to fill in: enter your own.
When and how
- Usually: at light trace.
- Also used: at thick trace.
- Mix it first with a little of the recipe’s oil, about a teaspoon of powder to a tablespoon of oil, so it spreads without specks.
Soap Queen supplier or guide, Faiola, Pure Soapmaking primary source
What it does to the recipe
- It changes neither the lye nor the water: it is only weight in the bar.
Worth knowing
- It speeds trace. Faiola, Pure Soapmaking primary source
- Skin allergy to it has been reported. CIR primary source
- In the US colloidal oatmeal is a skin-protectant drug ingredient: a soap that claims to protect or soothe skin with it is a drug. FDA OTC monograph M016 primary source
Spoons and drops
- 1 tsp ≈ 2.02 g
- 1 tbsp ≈ 6.06 g
- 1 cup ≈ 97 g
The Soap Kitchen supplier or guide
INCI name
Colloidal Oatmeal
Recipes that use it
Guides that discuss it
Sources
Lovely Greens, oatmeal soap: "Both oat flour and colloidal oatmeal are fine grades of oatmeal that you can barely feel in soap"; they come "without the abrasion" of larger pieces.
Soap Queen, exfoliants: fine powders mixed with a tablespoon of lightweight oil or water first; medium and large exfoliants at thin trace.
Anne-Marie Faiola, Pure Soapmaking (Storey Publishing, 2016), recipes in chapters 8–10. 100% Castile-Brine Stamped Cube: "1 tablespoon sea salt" dissolved in the water before the lye, for 33 oz of olive oil. Oatmeal Soap for Babies: "2 teaspoons bentonite clay dispersed into 4 tablespoons distilled water" and "2 tablespoons colloidal oatmeal" at thin trace, for 15.1 oz of oils whose olive oil is infused with "2 tablespoons Egyptian chamomile" in a teabag in 14.5 oz of oil, 2 hours in a double boiler. Nettle & Yarrow Upcycle: "2 teaspoons dried yarrow powder dispersed into 1 tablespoon apricot kernel oil" in one of two halves of 24.1 oz of oils. Buttermilk Honeycombs: "3 tablespoons honey" at thin trace for 25.1 oz of oils. Banana Cream Pie Layered Bars: "1.2 ounces banana, 1.5 ounces whipping cream, and 1.5 ounces water, pureed" at thin trace for 35.2 oz of oils, then the freezer "for 24 hours to avoid overheating from the sugars in the banana". Annatto-Yarrow with Embeds: "1 tablespoon spirulina powder" and "1 teaspoon yarrow powder", added "directly to the hot lye-water", for 7.1 oz of oils; "2 tablespoons poppy seeds" in one of two halves of 34 oz of oils. Cucumber Layers: "1 ounce cucumber puree" into the whole batch at thin trace, 22 oz of oils. Gardener Scrub with Coffee Grounds: 50 oz of oils, the batter divided "into four exactly equal sections", one each for "5 teaspoons paprika", "5 teaspoons ground orange peel dispersed into 1 tablespoon of canola oil", "5 teaspoons brewed coffee grounds" and "10 teaspoons green zeolite clay". Indigo-Annatto Negative-Space Funnel Pour: "1.5 tablespoons indigo powder" whisked into the lye-water and "1 tablespoon alkanet root powder dispersed into 1 ounce sunflower oil" at very thin trace, 35.2 oz of oils; "In order to bring out the best color for the indigo powder, the soap must go through a hot gel phase". Black Tea Funnel Pour: 5.5 oz of brewed black tea added at thin trace, 5.5 oz of water for the lye, 33.1 oz of oils. Goat Milk Sunset Burst: "0.7 ounce goat milk powder dissolved in 1 ounce distilled water" for 17.1 oz of oils and "1 ounce goat milk powder" for 25.2 oz, added at trace: "To help avoid scorching, this recipe incorporates the goat milk by using a concentrated solution of powdered goat milk."
Bramble Berry, colloidal oatmeal: "Use up to 5 percent of the total weight in soap".
Cosmetic Ingredient Review, Avena sativa (oat) ingredients (2014): kernel flour up to 84.4 % in skin cleansing products and kernel meal up to 1 % in bath soaps and detergents; "several reported cases of atopic dermatitis".
The highest concentration reported to CIR in industry surveys: what has been used, not a recommendation.
Anne-Marie Faiola, Pure Soapmaking (Storey Publishing, 2016): "1 teaspoon of sodium lactate for every 16 ounces (1 pound) of oils or 0.5 percent" (the two disagree: a teaspoon of the 60 % solution a pound is about 1.45 % of the oils, so neither is taken from this book); salt at "½ teaspoon per pound of oil", added to the water before the lye; "Salt decreases lather significantly"; salt bars are 80–100 % coconut oil at a high superfat. Chapter 5: coffee grounds, "For extra scrubbing power, use a coarse grind, while for gentle exfoliation, a super-fine espresso grind is best. Use the grounds to make coffee before adding them, or they might bleed brown halos into the final soap"; "Adding colloidal oatmeal can accelerate trace in your soap recipe; premixing with water can help avoid this"; honey, "start soaping with lye-water and oils both under 100°F (38°C). Add the honey at trace ... Once the soap is finished, place it in the refrigerator or freezer immediately to prevent overheating". Chapter 7: "A half teaspoon of sugar per pound of soap added to your lye-water can help your bar lather up."
US FDA, OTC monograph M016 (skin protectant drug products), M016.10(f): colloidal oatmeal, 0.007 percent minimum, is a skin-protectant active ingredient.
The Soap Kitchen, colloidal oat flour safety data sheet (2023): "Relative density 0.41g/ml."