Formulation of Labile Hydrophilic Ingredients in Multiple Emulsions: Influence of the Formulation's Composition on the Emulsion's Stability and on the Stability of Entrapped Bioactives

Abstract

Foods containing anthocyanins depicted significant health benefits in various studies. Since they are very unstable outside of their natural environment encapsulation into the inner aqueous phase of multiple emulsions should permit an optimal stability and allow for a target release. It was shown that a systematic adaption of the microstructure in double emulsions can be achieved by selecting adequate product- and process parameters: High pressure homogenizers and gear rim dispersing devices allow for the preparation of W₁/O-emulsions with similar droplet sizes. Higher specific energy inputs, emulsifiers with fast adsorption kinetics and adapted viscosity ratios enabled the production of smaller W₁- as well as W₁/O-droplets. The water soluble hydrocolloid pectin amide was successfully used for viscosity ratio adaption, microstructure variation and emulsion stabilization.

Keywords:

• anthocyanins
• bioactive ingredients
• encapsulation
• multiple emulsion
• stability

Acknowledgments

This research project was supported by the FEI (Forschungskreis der Ernährungsindustrie e.V., Bonn), the AiF, and the Ministry of Economics and Technology, AiF-Project No. 15612N. Further, the authors would like to thank Kaden Biochemical GmbH, Germany, for supplying bilberry extract and Herbstreith and Fox, Germany for supplying pectin. Finally, the authors would like to thank Sabine Leick (Institute of Physical Chemistry, TU Dortmund, Germany) for the spinning drop measurements and the TU München, ZIEL-Technology Unit, Germany, for supplying isolated β-Lactoglobulin.

Notes

From the Proceedings from Formula VI in Stockholm 2010.