Many industries use micro-encapsulation to convert liquid oil-in-water emulsions into powders containing particles that consist of oil droplets embedded in a solid wall material. The most common industrial technique used to accomplish this conversion is spray drying. The efficient production of high quality spray dried product depends on selection of the most appropriate spray drier design, operating conditions, and feed material. This invention improves the composition of the feed material used in spray drying, by improving the final properties of the powders produced and/or reducing the amount of solids required in the materials.

This novel invention improves the feed material by covering each individual oil droplet (or other type of particle) with a multilayer biopolymer membrane that is relatively thick and resistant to rupture prior to carrying out the drying process. These interfacial membranes can be designed to improve the economic, physicochemical and functional properties of the spray dried material.