Encapsulation of bioactive compounds using nanoemulsions

Roughly one-third of the food produced in the world for human consumption every year, approximately 1.3 billion tonnes, gets lost or wasted, according to the Food and Agriculture Organization (FAO). There is therefore an urgent need for new methods to preserve food. Encapsulation using nanoemulsions is a powerful technique for the protection of food-grade ingredients including vitamins, lipids, antioxidants and antimicrobial agents. In general, nanoemulsion systems demonstrate superior characteristics over conventional emulsions. This is due to their smaller droplet size, transparent optical properties, higher physical stability against droplet destabilization factors and improved bioavailability of the entrapped active ingredients. In general, nanoemulsions have been prepared with different sizes of droplets. However, a droplet size higher than 200 nm is generally preferred for food applications. Here we review nanoemulsion compositions, types of active ingredients, applications in different types of food systems, toxicological and safety aspects, and future directions.