Natural biopolymer gels for food product formulation

Texture is often one of the primary characteristics of product quality appreciated by consumers, and a source of innovation. It is the result of its structure. The use of polymers offers formulators multiple possibilities for constructing and managing product structure through the creation of gel networks in aqueous media. This is only possible if the conditions under which they are used are carefully controlled:

• the environment constituted by the other components of the formulation (solvent, dispersed components, etc.);

• process parameters used for manufacturing ;

• conditions of storage and use.

This dossier begins by outlining the general issues surrounding the texture and structure of products, and the role that polymers can play in the organization of gelled structures, depending on the purpose. The various classes of polymers and their origins are then presented in a non-exhaustive way, with the emphasis on biopolymers used in food formulations, but which are finding increasing application in other sectors, particularly in cosmetics and pharmaceuticals.

The physicochemical phenomena at the origin of gelation mechanisms are then developed both for simple systems – a polymer gelling in water –, for mixtures of biopolymers and for dispersed systems in which the dynamics of interactions between elements of the formula are decisive.

The main properties of gels, together with experimental measurement methods, highlight the importance of a formulation approach that takes the desired properties as the starting point for constructing the right product structure, integrating the possibilities offered by product/process interactions.

The authors draw mainly on their experience with food products to provide an approach that can be generalized to systems of a similar nature encountered in other sectors, in particular cosmetics, where the issues are comparable both in terms of the properties sought and the physicochemical phenomena involved.