Sunday, February 3, 2013

Where's the emulsifier? Play along!

Anonymous asked in this post: Speaking of oils and emulsifiers, I have a product that i am wracking my brain to work out what is acting as the emulsifier. Can anyone help me? Ingredients are: Water, sunflower oil, coconut oil, olive oil, wheatgerm oil, castor oil, sugar glycerin, chamomile, essential oils as fragrance, and colour. Any help will be appreciated. :)

Let's start at the very beginning (according to Julie Andrews, it's a very good place to start...) to analyze this product. I could give you an answer, but isn't it much more fun to figure it out?

What do we know about lotions? We know that lotions need at least three ingredients to be called a lotion - oil, water, and emulsifier. We also know that oil and water won't mix without an emulsifier, so that's necessary.

As an aside, I think there are four essential ingredients for a lotion - water, oil, emulsifier, and preservative because without the preservative you have a horrible concoction with a shelf life of maybe three days! 

What the heck is an emulsifier and why is it so necessary? An emulsifier is something that can make water and oil play nicely with each other. We know that oil and water don't mix, but we can make them mix by using an emulsifier and using heat, chemistry, and mechanics to make that lotion stay together. If we don't have an emulsifier, we can make oil and water mix temporarily - think of salad dressing and how we shake it - but that combination won't last long. Using a chemical emulsifier with heat and a lot of mixing makes for a more stable emulsion. (A chemical emulsifier should have a water loving head and a fat loving tail and they bring the water and oil together.)

The emulsifiers we use tend to be considered all-in-one emulsifiers - Polawax, Ritamulse SCG, BTMS-50, BTMS-225, and so on - but we can make our own emulsifiers using the HLB system. (I'm not getting into that that link for way more information.)

Beeswax is only an emulsifier when combined with borax for a water-in-oil product. Every recipe I've seen using beeswax as an emulsifier had something that looked like a co-emulsifier in the mix, like lecithin. (Click here for more information.) 

To sum this up - oil and water will not emulsify without an emulsifier. They might mix up for a while using heat or mechanical methods, but they will eventually separate into an oily layer floating on the top of the water.

Related post:
Emulsification: What's that then?

So here are the questions that come to mind for me...

1. What is the emulsifier in this product?
2. What is the preservative in this product?
3. What is the possible shelf life of this product?

1. There isn't one. How can the product work? It doesn't work. If it does, then the person who wrote up the ingredients list left out the emulsifier. There are some people who consider ethoxylated emulsifiers evil and others who don't consider any emulsifiers natural, so if this product creator wanted to appeal to those who might hate emulsifiers, they might leave it out. This is completely dishonest and makes me angry.

Can you go faster than the speed of light if you wish for it hard enough? Can you make 2+3 equal 7 if you really want it to equal 7? Why do we agree you can't violate the laws of physics or math, but wanting it bad enough will violate the laws of chemistry? You cannot make a long lasting emulsion without an effective emulsifier. And you cannot make a product not go mouldy by adding love or wishing on a star. Only an effective broad spectrum preservative or a proper combination of effective and proven preservatives will work. 

2. What is the preservative? Again, nothing is listed. If this is the case...

3. The shelf life is somewhere around 3 days without a preservative, if you keep it in the fridge. Even with the best manufacturing processes of heating and holding and using distilled water, you aren't going to get a week out of this. To sell a product like this is dangerous and the person who is doing so is leaving herself open for a world of pain when someone gets an icky infection!

The short answer is there isn't an emulsifier listed in this product. 

Related posts:
Shelf life of our products (part 1)
Shelf life of our products (part 2)
Determining the shelf life of our lotions
Emollients - oils, butters, and esters


SarahF said...

I wonder if the 'sugar glycerin' is actually Sucragel?

Anonymous said...

Thank you so much for answering my question! :)
I am new at formulating, but when i seen this product ingredient list it had me thinking what the? How does that work?
The company that sells this product is in Australia and is a supplier for nail and beauty products, and that is honestly all it says on the label. And i cannot find a use by date on it at all. I have another one of their products that says 'unigerm preservative' on it, but that also made me suss as that to me sounds like a trade name.. where is the chemical names? And no use by date on them either?
Lucky i didn't pay for them.. i won them in a nail art competition. They are selling their products all over Australia tho!
Thanks again for your help! And once again, awesome article, explained so well. :)

dublinmud said...

Wouldn't the sunflower oil be an emulsifier? (lecithin)

Things Are Not Always What They Seem said...

I was also thinking that sunflower oil would be the emulsifier, plus it may also be used as the preservative, as sunflower oil contains vitamin E, which is a preservative...

Susan Barclay-Nichols said...

No, sunflower oil isn't an emulsifier. It's an oil. If it contains lecithin, there isn't enough to act as part of an emulsifier. In an oil in water lotion, we use the HLB system to create an emulsifier with a low HLB emulsifier - which lecithin can be with a value of 4 or 7, amongst others - and a high HLB emulsifier. There isn't a high HLB emulsifier in this ingredient list, but even if there were, there's not enough lecithin in a bit of sunflower oil to act as an emulsifier. As I mentioned in the post, there isn't a proper emulsifier listed, which means this list is incorrect.