Β-lactoglobulin (β-lg) is the major whey protein abundant in cow’s milk. Β-lg is a lipocalin
whose structure contains β-barrel with eight antiparallel β-strands and one major α-helix at the
end of the molecule (Fig. 1). This protein has been widely used in the food and pharmaceutical
industries due to its rheological and structural characteristics (e.g. unfolding, aggregation and
gelation properties) [1].
Β-lg is capable of binding various hydrophobic ligands, such as fatty acids and vitamins,
carbohydrates, proteins and even inorganic elements [2]. At the present there is a gap with regard
to the knowledge of β-lg and polysaccharides interactions. Such an understanding of the impact
of interactions between β-lg and sodium alginate (Na-Alg) in food products and their biological
functions will help to design food products with optimized nutritional properties. We have studied
the influence of pH and molar ratio on the interactions between β-lg and Na-Alg mixtures. To
solve the complexity of such systems and to determine the three-dimensional models of the
obtained hetero-complexes, we have applied the small angle neutron scattering technique.

Fig. 1. UV-vis spectra of β-lg, Na-Alg and the mixture of β-lg and Na-Alg (1:1 ratio).
[1] C. Schmitt, S.L. Turgeon, Advances in Colloid and Interface Science. 167, 1–2 (2011), pp. 63-70.
[2] S. Le Maux, et al., Dairy Science & Technology. 94, 5 (2014), pp 409-426.