Formulation Basics: If Oil & Water Cant Mix, What Should We Do?

 Hi good morning all. As you know; today is the day most parents were waiting for in Malaysia; its the day kids go back to school after a year of being at home. The day where most don't want to send their kids to school coz of the covid cases that hasn't been going down but; deeply; im pretty sure parents are ‘relieved’ coz finally we can do our own things after close to 347days of being full time parents; housewife, and career women. (I know i am though im still worried about the cases :-() 

So anyways; just like everything is going back to ‘normal’ i thought of dedicating today’s post to going back to basics when it comes to formulating. If you haven't read my last week article about formulating; i suggest you read that first here.

As for today; lets continue from where we stopped last week.

So last week we spoke about water based products, and oil based products (anhydrous). So today; lets take it to the next lever; what if we wanted to add water based ingredient into anhydrous product? Or vice versa?

Well that depends on the product you want to make.

As you know; oil and water doesnt mix. And therefore you need the intermediator to connect them together. This is when different reactions need to happen for it to mix (besides manually mixing them)

Soap

So lets say if we wanted to make soap. Then the way oil and water would mix is by having a chemical reaction called saponification where the sodium hydroxide/ potassium hydroxide will have to breakdown double bonds in the fatty acids found in oils to mix with the water. I know its very ‘chemistry’ but thats what happens. 

So during this time; if you were to touch your cold process soap that was poured into the mold (as in tough the mold) it will be quite ‘hot’ even though you didn't add any heat to it. The heat; is from the reaction that happens in that 24 hours of molding. You can read more about cold process soap here.

Moisturizer 

Now oil and water can be mixed in a lot of different ways. So if lets say this time you didnt want to make soap. Maybe you just want to make lotion or cream or anything thats a mixture of oil and water; what do you use? well use an emulsifier! 

Emulsifier is a ‘chemical’ ( we call it chemical even though they are naturally derived because its a intermediator; and in science; it is chemical with atoms and all!) that is used to mix water and oil. There are many emulsifiers but if you wanted to mix equal amount of oils and water without the headache of learning the HLB chart; we use the emulsifying wax NF. Its a combination of few different ingredient that is done for us. When you use them; it will mix that two watery component (oil and water) into a thick cream like texture.

Toner

What If you just wanted to add few drops of essential oil into all water ingredient (lets say toner?) well that depends. If you prefer to mechanically shake the product before use; you can not adding anything. But if you wanted to make a stable well distributed product; we usually use emulsifiers like hydrogenated castor oil and polysorbate 20.

Balm

The same goes for water in oil. What if you wanted to add some liquid extract into a balm thats all oil based? Same thing; you could use polysorbate 80 or hydrogenated castor oil.

I want you to remember that BEESWAX is not an emulsifier ya. Its a hardener. Though it does look like its helping the oil and water to mix; its actually only during production. Over days or weeks the water and oil will separate causing the products to be not stable. Read more about it here

So there you go. Formulation basics as to how to mix oil and water.

Hope you found this article useful. Thank you so much for reading.

P/S: This is something that i teach in my formulation classes. All back to basics. If you would like to learn more about the classes please click here (if you cant attend the class no worries; over the course of few months i will be putting these kind of articles so you could start formulating at home:-)

Good luck;

Nisha