You can spend weeks perfecting a cosmetic formula. You can choose the best ingredients, create the perfect texture and package it beautifully.
But without the right preservative, all of that hard work could be undone.
If your formulation contains water (and most cosmetic products do), preserving it isn't optional, it's essential. A well-chosen preservative helps protect your product from bacteria, mould and yeast, keeping it safe, stable and effective throughout its shelf life.
Let's take a closer look at why preservatives are one of the most important ingredients in any formulation.
Why Do Cosmetic Products Need Preservatives?
Water is one of the best environments for bacteria, mould and yeast to grow.
That means products like lotions, shampoos, body washes, conditioners, serums and liquid soaps are all vulnerable to contamination if they aren't properly preserved.
And contamination doesn't just happen in the factory.
Every time someone uses a product, there are countless opportunities for microorganisms to find their way inside.
This can happen through:
- Fingers dipping into a jar
- Water getting into the container
- Air exposure every time the bottle is opened
- Manufacturing equipment
- Packaging during filling
What Happens If You Don't Use a Preservative?
A contaminated cosmetic product is more than just unpleasant.
It can lead to:
Skin irritation | Eye irritation | Infections | Bad odours | Colour changes | Product separation | A much shorter shelf life
In other words...
A beautiful formulation can fail completely if it isn't properly protected.
So, What Does a Preservative Actually Do?
Think of preservatives as your formula's security system.
Their job is to prevent bacteria, mould and yeast from growing inside your product while it sits on a shelf, or in someone's bathroom, for months.
At Brightpack, two of our most popular preservative options are:
|
Omnicare PEHG |
Omnicare IT |
|
|
INCI Name |
Phenoxyethanol, Ethylhexylglycerin |
Methylchloroisothiazolinone, Methylisothiazolinone |
|
Common Name |
PEHG |
MCI/MI or IT Preservative |
|
Type |
Broad-spectrum preservative |
Highly effective broad-spectrum preservative |
|
Appearance |
Clear, colourless liquid |
Clear to slightly yellow liquid |
|
Omnicare PEHG |
Omnicare IT |
|
This preservative prevents bacteria, yeast and mould from growing inside cosmetic products. It contains:
Together they help keep cosmetics safe throughout their shelf life. |
This preservative also prevents bacteria, mould and yeast from growing. It contains:
These preservatives are extremely powerful, which means only a very small amount is needed.
|
Which Preservative Should You Choose?
The answer depends on the type of product you're making.
|
Omnicare PEHG |
Omnicare IT |
|
Used in almost every type of cosmetic product including:
|
Mainly used in rinse-off products such as:
|
|
Suitable for both:
|
Only used in rinse-off products Not used in leave-on cosmetics because of strict regulations. |
When Should Preservatives Be Added?
Timing matters.
Both Omnicare PEHG and Omnicare IT should be added during the cool-down phase of manufacturing, typically below 40–50°C.
Adding preservatives while the formulation is still too hot may reduce their effectiveness, which is why they're usually one of the final ingredients added to the batch.
More Isn't Better
One of the biggest misconceptions in formulation is that adding extra preservative makes a product "safer."
It doesn't.
Every preservative has a recommended usage level that's been carefully tested for both safety and performance.
Typical usage levels are:
- Omnicare PEHG: 0.5–1.0%
- Omnicare IT: 0.05–0.1% (15 ppm active ingredients)
Using more than recommended isn't necessary and may not comply with cosmetic regulations.
Every Preservative Has Its Limitations
Just like every active ingredient has strengths and weaknesses, preservatives do too. Understanding these limitations will help you select the right preservative for your formulation instead of trying to make one preservative fit every application.
|
Omnicare PEHG |
Omnicare IT |
|
|
Why Does pH Matter?
A preservative can only do its job if it's working within its effective pH range.
Choosing a preservative that isn't compatible with your formulation's pH may reduce its ability to protect against bacteria, mould and yeast, even if you've added the correct amount.
Here's how our two preservative options compare:
| Preservative | Effective pH Range |
|---|---|
| Omnicare PEHG | Approximately pH 3–10 |
| Omnicare IT | Approximately pH 2–8, with best performance below pH 8.5 |
One of the reasons Omnicare PEHG is so widely used is its broad pH compatibility, making it suitable for a wide variety of skincare and personal care formulations.
Omnicare IT performs exceptionally well too, but it works best in formulations that remain below pH 8.5, making it an excellent choice for many rinse-off products.
Don't Forget the Challenge Test
Even the best preservative can't guarantee protection in every formula.
Different ingredients, pH levels and packaging can all affect how well a preservative performs.
That's why finished formulations should always undergo a Microbial Preservative Efficacy Test (Challenge Test).
This confirms that your preservative system is working effectively within your specific formulation and will continue protecting your product throughout its intended shelf life.
The Bottom Line
Choosing a preservative isn't simply about picking one off a shelf, it's about selecting the right preservative for your formulation, pH, product type and intended use.
At Brightpack, we stock preservative solutions for everything from lotions and serums to shampoos and body washes. Whether you're creating your first formulation or refining an existing one, we're here to help you choose a preservative system that keeps your products safe, stable and performing exactly as they should.