Emulsions, mixes of immiscible liquids such as oil and water, are found in products that range from pharmaceuticals and pesticides to make-up and mayonnaise. ‘Multi-emulsions’, multi-layered matryoshka doll style, oil-in-water-in-oil systems have seen growing interest from academics in recent years. However, current methods work only on large-scales and produce single multi-emulsions at slow rates.

Now, academics from the US West Coast have developed a process to solve some of the problem incolved in creating multi-emulsions. Their technology uses sequential, high-energy emulsification to create nanometre-sized droplets of oil, suspended in water droplets, which are in turn suspended in a second oil. This innovation opens the door for products such as novel encapsulated drugs and pesticides, or even for ultra-low-fat salad dressings.