Layer-by-layer emulsions backed for focused release in foods

The review – published in Current Opinion in Colloid & Interface Science​​ – offers an overview of the ‘layer-by-layer’ emulsification approach for the modification of food based emulsions.

Led by Dmitry G. Shchukin from the Max-Planck Institute of Colloids and Interfaces, Germany, the research team explains that layer-by-layer modification of emulsion surfaces allows for step-wise adsorption of various components – including polyelectrolytes, nanoparticles, proteins, enzymes, etc. – as the layer growth and allows the formation of multilayer shells with nanometer precision.

“The current level of the development in the food industry … requires not only the fabrication of the emulsion systems, but also their functionalization in order to impart it multifunctional properties,”​ note the researchers.

“One of the most perspective approaches to attain additional functionality to the emulsion particles is the use of the layer-by-layer (LbL) modification of their surface,”​ they explain. “This technique permits the step-wise adsorption of various components (polyelectrolytes, nanoparticles, proteins, enzymes, etc.) as the layer growth is governed by their electrostatic attraction and allows the formation of multilayer shells with nanometer (thickness) precision."​

The team noted that a potential benefit of using such emulsions as delivery systems is that they can be fabricated entirely from natural food grade ingredients (lipids, proteins, polysaccharides) using simple processing operations (homogenization, mixing).

“They could therefore be utilized in the development of … functional foods designed to combat diet‐related diseases, such as obesity, heart disease, cancer, and hypertension,”​ the authors explain.

Focused release​

Shchukin and his team note that there are several ways for triggering the release of the encapsulated loads – by employing either external or internal factors sush as changes in pH, or by action of enzymes in the emulsion shell.

“Delivery systems designed to control the digestion, release, and absorption of encapsulated lipophilic components within the gastrointestinal tract are being developed for a variety of applications within the pharmaceutical, biopharmaceutical, and food industries,”​ they note.

“They can be used to control the release of drugs and other bioactive components at specific locations within the gastrointestinal tract, such as the mouth, stomach, small intestine, or colon.”​

Source: Current Opinion in Colloid & Interface Science​​
Published online ahead of print, doi:
“Layer-by-layer coated emulsion microparticles as storage and delivery tool”​
Authors: Elena M. Shchukina, Dmitry G. Shchukin