Recent developments in encapsulation and release of functional food ingredients: delivery by design

The development of colloidal delivery systems (CDS) to encapsulate, protect, and release bioactive agents has exploded in recent years, as seen by the large increase in papers published in this area. These delivery systems include micelles, microemulsions, nanoemulsions, emulsions, multiple emulsions, solid lipid nanoparticles, protein nanoparticles, and biopolymer microgels. Despite this fact, it is unclear how many of these delivery systems are actually being adapted by industry, or if they are even suitable for commercial applications. Many of the CDS described in scientific manuscripts are prepared from ingredients that are not legally acceptable in foods, are fabricated using processing operations that are uneconomic or cannot be scaled up, or have properties incompatible with the intended final application. This article describes the principle of 'delivery by design' (DbD) as a more rational approach to create CDS with properties suitable for commercial applications.