“Associative interactions between
exopolysaccharides from lactic acid bacteria and milk proteins. Gaining
insights deployable in design of optimized food texture”
Chemically modified polysaccharides from plants or seaweeds are extensively used as biothickeners by today’s food industry. Their use is however, strongly restricted and food products enriched with these need to be labeled with E-numbers. Numerous studies have established that hetero-exopolysaccharides (HePS) excreted by various lactic acid bacteria strains have a similar impact on textural properties in fermented milk products. HePS are natural ingredients and generally recognized as safe (GRAS), and thus in situ production of HePS needs no declaration. The textural property of fermented milk products is an effect caused by complexation between HePS and milk proteins. However, the correlation at the molecular level between HePS-milk proteins interactions and the textural properties is poorly understood.
The project aims at gaining novel insight into protein binding by HePS, which is crucial to yoghurt texture. Experimentally we will screen for complexation between structurally characterized HePS and milk proteins. HePS-milk protein interactions will be characterized by various biophysical, micro- and macroscopic analyses. The project outcome will identify structural elements important for HePS-milk protein complex formation and will advance rational manipulation of systems to control yoghurt texture and may apply to other fermented milk and cereal-based foods without the use of additives.