Book excerpt: Stabilisers, thickeners and gelling agents are extracted from a variety of natural raw materials and incorporated into foods to give the structure, flow, stability and eating qualities desired by consumers. These additives include traditional materials such as starch, a thickener obtained from many land plants; gelatine, an animal by-product giving characteristic melt-in-the-mouth gels; and cellulose, the most abundant structuring polymer in land plants. Seed gums and other materials derived from sea plants extend the range of polymers. Recently-approved additives include the microbial polysaccharides of xanthan, gellan and pullulan. This book is a highly practical guide to the use of polymers in food technology to stabilise, thicken and gel foods, resulting in consistent, high quality products. The information is designed to be easy to read and assimilate. New students will find chapters presented in a standard format, enabling key points to be located quickly. Those with more experience will be able to compare and contrast different materials and gain a greater understanding of the interactions that take place during food production. This concise, modern review of hydrocolloid developments will be a valuable teaching resource and reference text for all academic and practical workers involved in hydrocolloids in particular, and food development and production in general.