hemicellulose

1. (biochemistry) A mixture of several plant polysaccharides, of smaller molecular weight than cellulose, that are soluble in dilute alkali; they are involved in the manufacture of paper, and are used in the production of furfural and ethanol.Examples: "The changes in texture that occur during ripening and cooking result from changes in the cell-wall materials, in particular the cement carbohydrates. One group is the hemicelluloses, which form strengthening cross-links between celluloses. They are built up from glucose and xylose sugars, and can be partly dissolved and removed from cell walls during cooking."