Steam treatment dissociates cellulose from hemicellulose and lignin for enzymatic hydrolysis to produce fermentable sugars. All plants contain lignin, hemicellulose and cellulose. These structural plant carbohydrates include pectin, lignin, cellulose, hemicellulose, muclinage, and gums. Carrot dietary fiber comprises mostly cellulose, with smaller proportions of hemicellulose, lignin and starch. Lignocellulose is composed mainly of cellulose, hemicellulose and lignin. Their cell walls consist of cellulose, hemicellulose, and lignin. The insoluble carbohydrates in soybeans consist of the complex polysaccharides cellulose, hemicellulose, and pectin. Natural fibers are composed by microfibrils of cellulose in a matrix of hemicellulose and lignin. This leaves behind the fibrous parts such as cellulose, lignin and hemicellulose. Cellulose and hemicellulose is degraded to aliphatic carboxylic acid soaps and hemicellulose fragments. Hardwoods are made up mostly of three materials&colon; cellulose, hemicellulose, and lignin. Diverse sugars comprise hemicellulose, whereas cellulose is derived exclusively from glucose. Bulking fibers can be soluble (e.g. psyllium) or insoluble (e.g. cellulose and hemicellulose). This structure then accumulates cellulose, hemicellulose and protein. The soluble fiber in psyllium is the polysaccharide heteroxylan, a hemicellulose.