The so-called “Drop-Test” does NOT test the quality of an emulsion. It will ONLY tell if a “water-in-oil” emulsion has been generated or not. If the drop stays intact, it is a “water-in-oil water” emulsion. If it “dissolves” quickly, it is an “oil-in-water” emulsion. To test its quality, put a small drop on a glass-slide after you have generated the emulsion. Smear it out with a coverslip and then place it over the emulsion. Inspect the emulsion with a microscope at 200-400x final magnifications. A perfect emulsion will have small uniform homogenous droplets. Read more about it in our Application Note.