ISBN 9783843946186

978-3-8439-4618-6, Reihe Verfahrenstechnik

Verena Johanna Wiedenmann
Building block and network properties of β-lactoglobulin gels and films as affected by solid lipid nanoparticles

191 Seiten, Dissertation Karlsruher Institut für Technologie (2020), Softcover, A5

Zusammenfassung / Abstract

One way to increase the nutritional value of food is to enrich it with bioactive substances. However, carrier systems are often required to protect the bioactive substances against external influences. Solid lipid nanoparticles (SLN) are one such carrier system. The literature has shown that carrier systems can enhance the mechanical properties of protein gels when particles interact with the protein matrix or weaken when particles do not interact with the protein matrix. In order to use a carrier system to increase the nutritional value of protein matrices, it is therefore necessary to know the effects of the carrier system on the protein structure. In this work, cold-set gels and films from ß-Lactoglobulin (BLG) were chosen as model matrices. The study focused on the impact of interactions between the particles surface and BLG and on the influence of interactions between the emulsifiers and BLG on matrix properties.

SLN were stabilized with lecithin and sucrose palmitate. Furthermore, either Tween 20 or BLG was used as the third emulsifier. This thesis was based on the assumption that Tween 20-stabilized SLN will not interact with the surrounding protein, while BLG-stabilized SLN will interact with the protein. It could be shown that SLN can be applied in protein-rich matrices. The changes in network properties after the introduction of SLN were caused by overlapping effects: by (1) adsorbed protein on the SLN surface, which can be controlled by emulsifier selection; and, to a lesser extent, by (2) increase in protein aggregate sizes by the presence of free emulsifiers. The findings in this thesis emphasize the importance of the choice of emulsifiers to stabilize carrier systems and the knowledge of their interactions with the surrounding ingredients. This knowledge can be used to design the properties of protein matrices in a targeted way.