Microstructure and rheology of whey protein based hydrogels

Year 2020, Volume: 48 Issue: 3, 301 - 307, 15.06.2020

Özgür Tarhan , Osvaldo Campanella

Abstract

Protein hydrogels have great potential for food and biomedical applications due to their ability to create three dimensional gel networks. A dairy industry by-product whey contains valuable proteins capable of forming gels with the ability of holding excess amount of water and entrap active ingredients. This enables a wide use of whey proteins for various applications in food formulations. Whey protein gelation is commonly promoted by heat and the gel characteristics can be enhanced by blending whey proteins with suitable carbohydrates. Mechanical properties and microstructure of gel networks determine their availability for target applications such as entrapment of active agents by maintaining their stability, target delivery and texture improvement of food products. The objective of this study was to investigate structural and mechanical features of whey protein -sodium alginate gels using microscopy, spectroscopy and rheometry. Rheological and structural properties of gels obtained by different preparation protocols and composition differed significantly. Porosity in the gel microstructure changed remarkably as the gel composition changed. Also, some conformational changes were tracked by studying the secondary structure of proteins during gel formation. Further research will focus on investigation of these whey protein-based gels for the entrapment ability and release behavior of bioactive components.

Keywords

whey proteins, gelation, sodium alginate, microstructure, spectroscopy

Supporting Institution

TÜBİTAK

Project Number

2219 Postdoctoral Research Grant

Thanks

The authors would like to thank Chia Ping Huang from Life Science Microscopy Facility, Dr. Patricia Bishop from Chemistry Department in Purdue University for their technical assistance in cryo-SEM, and CD analyses, respectively. The author Dr. Ozgur Tarhan was financially supported by The Scientific and Technological Research Council of Turkey (TUBITAK) for postdoctoral research in USA.

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