Explain about the Gelation?

Gelation refers to the process where denatured molecules aggregate to form an ordered protein network. Proteins can form a well-ordered gel matrix by balancing protein-protein and protein-solvent interactions in food products. These gel matrices can hold other food ingredients in producing food products, like gelatin, yoghurt, comminuted meat products, tofu and bread doughs. Gelation is an important functional property of several proteins that plays a major role in preparation of many foods, including various dairy products, coagulated egg whites, gelatin gels, various heated, comminuted meat or fish products, soy bean protein gels, vegetable proteins texturized by extrusion or spinning and bread doughs. Protein gelation is utilized not only for the formation of viscoelastic gels but also for improved water and fat absorption, thickening, particle binding (adhesion) and emulsion or foam stabilizing effect. While studying about gelation, it is also important to differentiate it from other related phenomena in which the degree of dispersion of protein solution is decreased. For e.g.

• Association: refers to changes occurring at subunit or molecular level.
• Polymerization or aggregation: involves formation of large complexes.
• Precipitation: includes all aggregation reactions with total loss of solubility.
• Flocculation: random aggregation reaction in the absence of denaturation; often occurs because of suppression of electrostatic repulsion between the chains.
• Coagulation: random aggregation with denaturation and aggregation reactions where protein-protein interactions predominate over protein- solvent interactions and forms a coarse coagulum.