Why Ingredient Substitutions Don't Always Work

I regularly get asked if it is possible to switch one ingredient for another in different products.

Sometimes it is in regard to a formula I have shared here on the blog or published in my e-books, but also about formulas others have created or are in the process of creating.

What Makes Sense

In many instances, it makes all kinds of sense to assume ingredients of the same type are interchangeable. For example, switching apricot kernel oil for sweet almond oil is hardly likely to make a huge impact on the outcome of a face oil or even an emulsion.

One could even get a little racy and exchange the apricot kernel for an oil with an entirely different lipid profile and still be successful. Imagine how pracaxi or babassu oil might influence the viscosity, feel and performance of an emulsion.

But in some instances, substituting a single ingredient will change not only the function and texture of a product, it may even result in a massive fail.

To make things even more frustrating, it might even be an ingredient that is used in very small percentages.

To illustrate, let's take a brief look at gums.

A Gum is a Gum is a Gum, Right?  

Gums are generally used as texturisers and thickeners, but some gums offer additional (and super cool) functions.

There's a pretty wide selection of gums available on the cosmetics ingredients market these days
  • acaia (also known as gum arabic)
  • agar agar
  • xanthan
  • guar
  • carragheenan
  • cellulose gum
  • konjac glucomannan
  • locust bean
  • sclerotium

These are all plant-based, often categorized as natural, and many can be spotted on the ingredients label of cosmetics products.

A lot of them are used in foods as well. Check the ingredients label of your fave chili sauce and you will in all likelihood find xanthan listed.

While some of these gums have similar properties, they are not interchangeable.

When Guar is the Star

I've worked with guar gum in numerous ways over the years and find it highly beneficial for some hair products because of the super duper conditioning properties it brings to a mix when it is prepared and added using a specific (proprietary) method.

You'll find an article I wrote about it a few years ago (link below) where I was so pleased with the results, I dubbed guar the 'natural alternative to silicone'.

I know you've already guessed what comes next.

If the guar is included in a formula specifically for its hair conditioning properties, replacing it with any other gum is going to result in seriously unsatisfactory conditioning action.

This will in all likelihood be followed by unpleasant utterances and stamping of feet.

Because (not all) gums are interchangeable in any given formula.

Then How Do We Know When We Can Substitute an Ingredient?

I wish I could give you an instant, snap-and-everything-is-perfect solution, but the best I can do is offer you these tips:

If you are following a formula someone else has developed: stick to the suggested ingredients substitutions (if there are any). Alternatively, be prepared to do some experimenting (which can be loads of fun and very educational). Enter this 'substitutional experimentation phase' with a neutral mind and low expectations. You may have to bin the batch, but may also discover you've created something fabulous.

If you are developing your own formula, set aside some time to get up close and personal with each ingredient you want to include. Make small A/B (side by side) test batches and see how your selected ingredients and possible substitutions react in different mixtures, at different temperatures, and using different methods. When your experiments are finished, you may very well find you've outdone yourself with your own brilliant formulating. Most importantly, enjoy the process!

Do Tell

Are you a fan of substituting ingredients in formulas? What has been your boldest substitution and how did it turn out? Please feel free to add a comment below.

More Stuff

What you need to know about natural gums: Skin Chakra
Natural gums and their application, Journal of Scientific and Innovative Research
The plant based alternative to silicone (on this blog)