In Part 1 of Emulsifiers Explained, we covered the basics: what an emulsifier is, why it matters and some of the things you need to consider when choosing one.
But knowing that you need an emulsifier is only the beginning.
Start looking at different emulsifiers and you’ll quickly notice that they can look different, behave differently and be suited to very different formulations.
So, what actually makes one emulsifier different from another?
Welcome to Part 2.
How Are Emulsifiers Classified?
The word emulsifier covers a much broader group of ingredients than you might initially expect.
Emulsifiers can be grouped into different categories according to factors such as their function, chemistry, physical form and application.
Understanding these classifications can make ingredient selection feel much less confusing. Instead of simply seeing a long list of unfamiliar ingredient names, you can start to understand where an ingredient fits and why it may be used in a particular formulation.
Let’s start with one of the easiest differences to recognise: physical form.
Solid Emulsifiers and Supporting Ingredients
Some ingredients used in emulsification systems are supplied in solid forms such as waxes, flakes, pellets or powders.
Examples you may come across at BrightPack include:
Solid ingredients in an emulsification system can contribute to characteristics such as richer textures, increased viscosity and stability.
You’ll commonly find these types of ingredients being used in products such as creams, lotions, moisturisers and conditioners.
But here’s where things get interesting.
Just because several ingredients are involved in an emulsification system doesn’t mean they are all doing exactly the same job.
Some may be responsible for creating the emulsion, while others support it, build viscosity or contribute to the texture of the finished product.
We’ll get into those differences in Part 3.
Liquid Emulsifiers and Solubilisers
On the other side, you’ll also find liquid emulsifiers and solubilisers.
Examples include:
PEG-40 Hydrogenated Castor Oil
These ingredients can be useful when working with lighter, lower-viscosity products, including sprays, toners, body mists and facial mists.
A solubiliser can help disperse small amounts of oil-soluble material, such as fragrance or essential oils, into a water-based formulation.
This is why a product such as a body mist requires a very different formulation approach from a thick body cream – even though both might contain water and an oil-soluble ingredient.
Physical Form Is Only One Part of the Story
Solid versus liquid is an easy place to start, but it’s far from the only way these ingredients can be understood.
Emulsifiers can also be classified according to factors such as their function, the type of emulsion they create or support, their ionic charge and their origin.
You may come across terms such as:
Primary emulsifier.
An ingredient responsible for creating and helping maintain an emulsion.
Co-emulsifier.
An ingredient that works alongside a primary emulsifier and can help support stability, viscosity and texture.
Solubiliser.
An ingredient used to help disperse small quantities of oil-soluble materials into water-based formulations.
You may also see terms such as oil-in-water (O/W), water-in-oil (W/O), non-ionic or cationic when researching ingredients.
If those words sound technical right now, that’s okay.
The important thing at this stage is simply understanding that “emulsifier” doesn’t describe one single type of ingredient or one single function.
Why Does Classification Matter to a Formulator?
Imagine you're developing two products: a lightweight body lotion and a hair conditioner.
Both may contain oil and water, and both require an emulsification system.
But that doesn't mean you should automatically use the same ingredients in both.
The type of product you're making, its desired texture and viscosity, the other ingredients in the formulation and the performance you're trying to achieve can all influence the emulsification system you choose.
Learning how emulsifiers are classified gives you a framework for understanding those differences.
Instead of asking:
“Which emulsifier should I buy?”
You can start asking:
“What do I need this ingredient to do in my formulation?”
And that's a much more useful question.
From Ingredient Names to Better Formulating
When you’re starting a beauty or personal-care business, ingredient names can feel like another language.
At BrightPack, we want to make that language easier to understand.
Along with supplying raw materials to small businesses and start-ups, we want to help our customers better understand what they’re buying and why they might use it. That’s why this series has been developed with technical input from our in-house chemist, taking some of the more complicated parts of formulation and breaking them down into manageable pieces.
You don’t need to learn everything at once.
Start by understanding the basics, then build from there.
And now that we know emulsifiers can be classified in different ways, there’s one particularly important question we need to answer:
What job is each one actually doing in your formulation?
Coming next: Emulsifiers Explained Part 3 — What Is Your Emulsifier Actually Doing?
Next week, we’ll unpack the difference between primary emulsifiers, co-emulsifiers and solubilisers, before looking at oil-in-water and water-in-oil emulsions – and why understanding these differences can help you make more informed formulation choices.