Polysaccharide-based microgels and nanogels for the food sector

Topic  14
Main supervisor A.Radulescu (a.radulescu@fz-juelich.de)
MLZ institution FZJ
Local supervisor 1

Konstantinos Sotiropoulos


Hyad Mike

Local supervisor 2 Aristeidis Papagiannopoulos
Institution National Hellenic Research Foundation
Local supervisor 3
Local supervisor 4

Polysaccharide-based microgels and nanogels for the food sector


Natural food products and developed food components show a hierarchical organization of different structures and morphologies. Small-angle neutron scattering (SANS) is a dedicated technique to structural characterization of such complex multi-component systems over a wide length scale from nm to microns. Moreover, using the contrast variation and contrast matching methods, selected constituents in a complex system can be labeled by H/D isotope exchange and be made “visible” or “invisible” in the scattering experiment without chemically altering the system. Therefore, SANS is particularly suitable in solving the structure and morphology of hydrocarbon materials and can provide unique information on the relationship between nanoscopic / mesoscopic structural characteristics and macroscopic functional properties of food systems.

HYAD MIKE is a nutritional supplements’ manufacturing company producing a variety of products in the forms of capsules, tablets and liquids. The main purpose is to provide innovative solutions for the food sector developing formulations with ingredients in correlation to their physicochemical and biokinetic properties. Many ingredients (herbal extracts containing flavonoids, probiotics, enzymes) used broadly in nutritional supplements are studied extensively due to their potential beneficial properties in aspects of human health including immune system, inflammations, oxidative stress, cognition, digestive health etc., showcase however limited bioavailability as a result of low water solubility and degradation caused by pH and temperature changes. Encapsulation of these bioactive materials in microgels/nanogels could enhance stability and bioavailability as well as provide controlled-release features. In addition, use of food-grade microgels as emulsion-stabilizers in oil-in-water/water-in-oil liquid systems is a field of interest for the food industry combining optimal stability providing biocompatible materials [1].

Food polysaccharide-based microgels and nanogels will be prepared from water-in-oil emulsions with ionic crosslinking as this method allows for dense particles while it is versatile and ecofriendly. The microgels/nanogels’ internal structure and stimuli-responsive properties to external triggers (e.g. pH and ionic strength) will be correlated to the kind and amount of used polysaccharide (carrageenan, alginate, pectin), ionic (CaCl2, KCl) or macroionic (chitosan, proteins) crosslinker and oil-to-water volume fraction.

SANS with contrast variation / matching will be applied for the characterization of morphology in these materials.

[1] Dickinson, E. Trends in Food Science & Technology 43 (2015) 178