I'm trying to produce a stable, high-viscosity oil-in-glycerin emulsion using lecithin and MCT oil.
The problems: Even when it seems to start working, my mixture often liquifies the moment I remove the source of agitation (a hand mixer). Mostly, I get a slightly viscous fluid that seems semi-stable, though it never progresses past this point, and I can see superfine 'flecks' of oil on the surface of the emulsion.
I've tried increasing the initial viscosity with the addition of tapioca starch, but this isn't yielding adequate results.
What am I doing wrong? My suspicions:
- I'm using the wrong surfactant. (I want a 'natural' emulsifier that's also easy to understand on product labels, so lecithin seemed a good fit.)
- I'm overdoing the lecithin (is using too much of a surfactant something to worry about?).
- The hand blender is applying the wrong kind of shear (sometimes I get better results making, say, mayo using a whisk).
- The MCT is not viscous enough to start the process off.
- The polarity/surface tension of the glycerin requires a different strategy to making an analogous emulsion such as mayonnaise. I can see hints of this in the way the oil 'takes'; it seems less enthusiastic, shall I say, to incorporate itself.
- I'm barking up the wrong tree entirely.
Either way, I know this should work, and I've seen it almost work. I just don't know what I'm doing wrong, because isolating the variables is hard when it's not possible to isolate a certain variable beyond certainty (a hand blender; I mean, c'mon).
Optional reading: First off, I'm super new at this. I'm not a chemist. I have a rudimentary knowledge of emulsification: partitioning of immiscible liquids in shells of surfactants surrounded by a continuous medium; the higher the intermolecular impact velocity the better (right?), so high sheer and high initial viscosity are desirable.
Anyway, help would be immensely appreciated!