Properties and Applications of Gelatin, Pectin, and Carrageenan Gels

This chapter focuses on biopolymeric hydrogels, especially gelatin, pectin, and carrageenan, which are widely used in the food industry. Gelatin is a product of the structural and chemical degradation of collagen. Gel strength and viscosity are the most important physical properties of gelatin. Pectin is a structural hetero-polysaccharide contained in the primary cell walls of terrestrial plants. Pectin is present in all plants, but the content and composition varies depending on the species, variety, maturity of the plant, plant part, and growing condition. Carrageenans, also known as carrageenins, form a family of polysaccharides obtained by extraction of various species of red seaweeds. Carrageenan is a mixture of water-soluble, linear, sulfated galactans. Pectin, carragennans, and gelatin are commercially important hydrophilic polysaccharides and have wide applications in the food, pharmaceutical, cosmetic, and biotechnology industries as gelling, thickening, stabilizing, and emulsifying agents.