Almost instant results!
This shows a picture of the 2 boiling tubes used in this version of the emulsion test. Only a small amount of test substance is needed (1 drop of cooking oil, in this instance), and after shaking this with a few ml of ethanol (purity not necessary - so industrial methylated spirits (IMS) can be used. It is then left to settle.
In the picture below, note the clarity of both the ethanolic solution and the water which almost fills the second tube.
In the picture below, note the white emulsion (opaque suspension of oil in water) which forms when the contents of the other tube are gently poured into the tube of water.