What are active ingredients, and when do I add them?
Short answer
Actives are the ingredients chosen for a specific effect, such as panthenol, peptides or niacinamide. Most are heat-sensitive, so they go into the cooling product at 38–40 °C.
Explanation
Examples from the book: D-panthenol for barrier repair, allantoin and bisabolol for soothing, niacinamide for sebum regulation, salicylic acid and Azeclair for problem skin, caffeine for puffiness, and peptides such as GHK-Cu, Argireline, Matrixyl and Progeline for aging concerns.
Long exposure to heat can break them down, so they're added to the cooling emulsion, typically at 38–40 °C, before the preservative at about 35 °C. Peptides are stirred in by hand or on the lowest speed so high shear doesn't denature them.
What to do
- Dissolve hard-to-dissolve actives (Azeclair, salicylic acid, caffeine, troxerutin) in 5–10 g of the water phase first, warming to 40 °C if needed.
- Add actives one at a time.
Source: The Big Book of Homemade Skin Care — Barrier Repair Cream · Cellular Renewal Elixir · Copper Peptide Renewal Serum