% of emulsifier for cream? New to this!

[throughthebarricades]

Hi,

I've been trying to write a recipe for a cream/thick lotion. I checked out Swift's blog and she suggests that for e-wax "you are going to use your emulsifier at 25% of the oils + butters amount. So if you are using 20% oils + butters, you're going to use 5% emulsifier".

My problem is that I want to use a higher % of oils and butters than 20% (my oil phase is already at 34%), and so the 25% of oils and butters logic puts my emulsifier at 8.5%. The emulsifier I want to use (glyceryl stearate and PEG 100 stearate) says the recommended usage is 1-5%.

So basically what I am asking is:

How do you know how much emulsifier to use? Does it have to be based on the % of ingredients in the oil phase? Does it differ depending which emulsifier you use?

Here's a link to the emulsifier I am talking about, if that helps: http://www.lotioncrafter.com/lotionpro-165.html

Any help would be appreciated

 

[SudsyKat]

I am definitely not an expert on this topic, but I believe that different emulsifiers will have different usage rates. The 25% figure is a rule of thumb and probably applies more to the "all purpose" type emulsifiers (ewax, polawax, etc). For "fancier" emulsifiers, I think you may have to actually do some calculations using the HLB system. Swift has lots of information on it, but frankly, I haven't been brave enough to delve into that kind of thing. You have to find out what HLB value is required by each of your oils, add them up, and then find the blend of emulsifying agents that fits that HLB requirement. Since you're already looking at a particular emulsifying blend, I'm not sure how that fits into the puzzle. Like I said, I'm no expert, but that's what i know. I hope I've been more helpful than confusing. I feel like I need to put my hands over my mouth now. For heavens' sake, someone who knows what they're talking about, please take over!!

 

[throughthebarricades]

Thank you! Funnily enough, about 15 minutes before I got the topic reply email I came to the same conclusion by doing some more research. I didn't quite realize just how complicated using certain emulsifiers was. I will try to learn the HLB system... looks a bit scary but here's hoping for the best