Sunday, February 13, 2011

Learning to formulate: Modifying your oil phase

While making our basic lotion the other day, we had a decision to make. Do we substitute 2% IPM for one of the oils or do we add it to the oil phase as an extra 2%? We addressed the substitution issue on Friday, so let's take a look at increasing your oil phase today. 

If you include 2% IPM and add it to the oils, you need to increase the emulsifier by 0.5% (if you're using Polawax or e-wax). Which means you need to remove 2.5% from the water phase (2% for the IPM, 0.5% for the increased emulsifier). THIS IS VITAL! Every change you make to your oil phase comes out of the water phase in exactly the same amount. 

HEATED WATER PHASE - notice the reduction of the water amount
53.5% water
10% aloe vera
3% glycerin
0.5% allantoin

HEATED OIL PHASE - IPM added at 2%, so emulsifier is altered upwards by 0.5% 
15% rice bran oil
2% IPM
5% mango butter
3% cetyl alcohol
6.5% emulsifier

If we add 2.5% to the oil phase, we remove 2.5% from the water phase. If we add 5% to the cool down phase, we remove 5% from the water phase.

What if you want to add more to the water phase to make it thinner? Then I'd suggest starting with a base recipe that contains more water. Or you could modify it without increasing the water phase but leaving out your thickener (like stearic acid or cetyl alcohol), taking out the heavier butters and replacing them with oils, or using lighter oils. Or you could modify the product to decrease the oil phase and increase the water phase. More about that in the coming days....

SPRING TIME BODY LOTION (IPM EXTRA) 
HEATED WATER PHASE - notice the reduction of the water amount
51% water
10% aloe vera
3% glycerin
0.5% allantoin

HEATED OIL PHASE
15% rice bran oil
2% IPM
5% mango butter
3% cetyl alcohol
6.5% emulsifier

COOL DOWN PHASE
1% fragrance or essential oil
0.5% preservative
2% panthenol
0.5% chamomile extract

That was easy, eh? Join me tomorrow with more fun learning to modify your oil phase even further! 

1 comment:

Mychelle said...

This is an issue I've been thinking a lot about this week! I want to add IPM to my body butter and whether to take it from the oil phase or increase the oil phase is a big decision. First I'm going to try subtracting it from my oils as the butter is already very thick. I might just try it both ways. I'm glad I'm not alone in thinking this is a big decision needing serious consideration. Thank you Susan. Your blog is awesome! And I'm really looking forward to the rest of this series and the duplicating series.