Hemicelluloses
Hemicelluloses are polysaccharides tightly associated with lignin and cellulose in the cell walls of all plants and some seaweeds, forming the matrix that gives plant tissues their structure. Their composition differs between plants and shifts with environment, growth and maturation; predominant sugars include D-xylose, D-glucose, D-mannose, L-arabinose, D-galactose, glucuronic and galacturonic acids, L-rhamnose, L-fucose and 4-O-methyl-glucuronic acid. In foods they contribute dietary fibre, influence texture and water-holding in wholegrain products, and serve as raw material for prebiotic xylo-oligosaccharides. Processing enzymes target them to improve extraction and digestibility.