ABSTRACT
This chapter describes the structure of xylan-type hemicelluloses, the influence of the composition and structure of xylan on film properties and approaches to improve the xylan's film-forming abilities and the films' properties. The poor water vapour barrier properties of xylan films may be owing to the hydrophilic hydroxyl groups in the xylan polymer. Considering the abundance, low cost and biodegradability, xylan as one of the important polysaccharides has attracted more and more interest for producing xylan-based films for packaging. Different plants and various isolation and purity methods could yield the various chemical compositions of xylan; consequently the different structure of xylan could have an important influence on its properties. Another approach to reduce the moisture sensibility of xylan films was adding lipids, which resulted in the formation of emulsion-based films. The additives may improve some other properties such as film formation ability, water vapour barrier property and homogeneity of xylan films.
