Permanent suspension of cocoa powder into water
Sounds like you need a food-grade surfactant. Maybe you could try lecithin?

The problem is that cocoa powder is mostly made of stuff that is not soluble in water (hydrophobic). So, to create the emulsion, you will need to "package" the powder molecules in something they are soluble in. You could either use a surfactant directly, or build up in layers using fat molecules and proteins, with a surfactant around the whole package.

Lecithin would be a good starting choice since it is FDA approved and used in lots of products already.

I would try this:


Add lecithin in gradually larger amounts until the suspension worked (you will have to try different heat/pressure and emulsification treatments - consider high-pressure homogenization as well.)
Add some whole milk (we are looking for the fat molecules and proteins) and see if you can find an acceptable milk/lecithin ratio that tasted good and that was still stable.


If that doesn't work, your other option is to modify the cocoa powder granule surface so that it is hydrophilic. That means you will need to add polar functional groups. One way to do that is with an acid (citric, for example), but you will add a sour taste which might be hard to get rid of. There is a patent for an approach using enzymes, but I don't know which one they used (it just refers to "starch degrading," "protein degrading," and "cell-wall degrading" enzymes), or how well it works.