Emulsifiers

An emulsifier is an ingredient that lets oil and water stay mixed instead of separating. Each molecule has a water-loving end and an oil-loving end, so it surrounds the oil droplets and holds them evenly through the water. This is what gives a lotion or cream its smooth, uniform texture.

A common starting point is about 5 to 10 percent emulsifying wax for a lotion that is roughly 75 percent water and 25 percent oils. A lighter, runnier lotion can use a little less, around 3 to 6 percent. Follow the suggested range on the listing and adjust to the texture you want.

Both are solubilizers that disperse oil into water, but they suit different oils. Polysorbate 20 is lighter and works well with lightweight fragrance and essential oils in sprays and mists. Polysorbate 80 is better suited to heavier oils. The right one depends on the oil you are trying to blend in.

The two most common reasons are too little emulsifier for the amount of oil, and stopping mixing before the emulsion cooled. Make sure your oil and water phases are near the same temperature when you combine them, use enough emulsifying wax, and keep stirring until the mixture is completely cool.

A solubilizer is a type of emulsifier used to disperse a small amount of oil, such as a fragrance or essential oil, into a mostly water product while keeping it clear. It is what you use for a room spray, a face mist, or a micellar water, rather than a full emulsifying wax.

HLB, or Hydrophilic-Lipophilic Balance, is a scale from about 1 to 20 that shows how much an emulsifier favors water versus oil. A higher HLB suits oil-in-water systems like most lotions; a lower HLB suits water-in-oil systems. It helps you pick or pair emulsifiers for a stable formula.

Emulsifying wax is for water-containing lotions and creams. A traditional anhydrous body butter made only of oils and butters has no water, so it needs no emulsifier. If you want a whipped lotion body butter that contains water, then yes, you use an emulsifying wax and preserve it.