Formulating with coconut and oat milk extracts

Milk extracts sit in the part of a formula that most affects how a finished product feels: the phase that carries water, sugars and proteins into an emulsion. This article covers what they are for, where they go in the process, and the questions worth asking your supplier before you buy. It is written for formulators and small brand owners working on creams, cleansers and bath products.

What a milk extract is, in formulation terms

The word "milk" here describes character, not dairy content. In cosmetic use, a milk extract is a water-based preparation carrying the soluble fraction of a plant material — the part responsible for the soft, slightly opaque feel the name suggests. Coconut and oat are the two most commonly used in personal care.

That matters for one practical reason above all others: they are water-phase materials. They go where your water goes, they bring water's problems with them, and they cannot be treated like an oil.

Where they sit in the process

As general industry practice, water-soluble botanical preparations are handled the same way regardless of which plant they came from:

• They belong in the water phase, not the oil phase.
• Many are heat-sensitive, so they are commonly added after the emulsion has been formed and cooled, rather than being boiled along with the water. Adding a delicate material at high temperature is the most common way its benefit is lost before the product is even filled.
• They raise the microbiological load of the formula. Any product containing water needs an effective preservative system, and a nutrient-carrying extract makes that requirement more pressing rather than less.
• They can affect viscosity and clarity. Build them into a trial batch before you commit to a full production run.

Every one of those points is general practice for the class. The handling conditions for a specific batch — the temperature it tolerates, how it behaves with your particular preservative — is a question for the documentation supplied with that batch, and it is worth asking for in writing.

Coconut Milk Extract

Cerium's catalogue describes Coconut Milk Extract as nourishing and moisturising, soothing to dry and sensitive skin, a gentle cleanser and exfoliator, and as improving skin barrier protection.

In practice, that combination points at three briefs. The first is a rich body cream or lotion where the claim is comfort rather than performance. The second is a gentle cleanser, where a material that cleans without stripping is the whole point of the product. The third is bath and shower, where the soft, milky character is what the customer is buying, and where it is also the most visible.

Oat Milk Extract

The catalogue is narrower here, and deliberately so: best for soothing dry, sensitive skin, and improving skin barrier protection.

Oat has a long association with sensitive-skin products, and the reason is worth understanding rather than repeating. Barrier-supporting materials tend to be bought for what they prevent — tightness, itch, the reaction a customer had to something else — rather than for a visible result. That shapes how you should write the claim. "Soothing" is defensible and is what the material is for. "Treats eczema" is a medical claim and belongs to a different regulatory category entirely.

If you are building a sensitive-skin line, oat is usually the first thing to trial and it pairs naturally with the rest of a barrier-focused formula.

The questions to ask before you buy

Milk extracts vary considerably between suppliers, more than most categories, because "milk extract" is a description of character rather than a standardised specification. Before committing to a production quantity, ask for:

• the documentation for the batch you are buying, not a generic sheet;
• the recommended handling and storage conditions;
• guidance on the use level, and confirm it against your own stability testing;
• confirmation of how it behaves with the preservative system you already use.

A supplier who can answer those quickly is worth more than one who is a little cheaper. If you are formulating to sell in Kenya, you will also want to check your finished product against the relevant national standards for cosmetics before it goes to market — that obligation sits with the brand, not with the raw material supplier.

Sourcing

Cerium supplies Coconut Milk Extract and Oat Milk Extract from Nairobi, alongside the natural extracts, carrier oils and butters that usually go into the same formula. If you are working on a soothing cream, a gentle cleanser or a bath product and want to talk through what goes with what, send the brief through the enquiry form and the team will come back to you.