When you want to make an oil in water emulsion you need ingredients (emulsifiers) that can bind a little bit of oil into a lot of water. In old money when HLB (hydrophilic, lipophilic balance) was the main ingredient selection tool, emulsifiers having a HLB of between 6-9 would be chosen. However, when you are trying to get a little bit of water into a lot of oil you need a different sort of emulsifier, one which favours the oil phase, one with a HLB at the bottom end of the scale – between 3-5 and that’s where Soya Lecithin comes in.
Most of the time we like to make oil in water emulsions as these feel light and un-claggy on the skin but there are times when you need the oil, say in an ointment, in balms, butters and waxes used for very dry skin or when you just HAVE to include a water based ingredient into your formulation.
I use soya lecithin when I want to add honey to my lip and body balms. This is because honey is a sugar/ water mix and tends to sit on top of the oils if you don’t add a little bit of chemical diplomacy into the mix.
Soya lecithin is a sticky, smelly, yucky-brown ingredient that won’t suit all formulations but I find that with the right handling it helps create some wonderful home-made anywhere balms. I think that while these balms look professional they have just enough home-made charm about them to maintain their authentic, honest and 100% natural appeal.