Proteins and emulsifiers at liquid interfaces

✍ Scribed by Peter Wilde; Alan Mackie; Fiona Husband; Patrick Gunning; Victor Morris

• Book ID: 104011670
• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 987 KB
• Volume: 108-109
• Category: Article
• ISSN: 0001-8686
• DOI: 10.1016/j.cis.2003.10.011

✦ Synopsis

The interfacial properties of proteins and emulsifiers have been studied extensively in the field of food colloid research. Emulsions form the basis of a huge range of food products and are generally stabilised by either protein andyor emulsifiers. Proteins have been shown to stabilise emulsions by forming a viscoelastic, adsorbed layer on the oil droplets, which form a physical barrier to coalescence. Emulsifiers can be oil or water soluble, forming a fluid, close-packed layer at the interface with a low interfacial tension. This results in an emulsion with a small droplet size distribution, stabilised by the fluid Gibbs-Marangoni mechanism or weak electrostatic repulsion. In real food emulsions, there is usually a mixture of proteins and emulsifiers competing for the interfacial area. This can produce a finer emulsion, however, the emulsifiers break down the viscoelastic protein-adsorbed layer, resulting in an emulsion with reduced stability. We present a review recent work that aims to characterise the composition, structure and physical properties of mixed protein-emulsifier interfaces, in an effort to understand the mechanisms behind the stability behaviour of food emulsion systems.