Comparison between Cellulose Blend Films Prepared from Aqueous Sodium Hydroxide Solution and Edible Films of Biopolymers with Possible Application for New Food Materials

Cellulose treated by a steam explosion method can be dissolved into aqueous sodium hydroxide solution. The regenerated cellulose shaped from the cellulose-dissolving system can be used as a food material with various shapes, such as fiber, film, and particles. In the present study, the cellulose was blended with polysaccharides, and the structure and mechanical properties of cellulose-polysaccharide blend films were compared with commercial edible films. The tensile strength, tensile elongation, and bursting strength of cellulose-starch blend films in wet conditions were comparable to those of sheep casings and collagen films. In the viscoelastic measurements, mechanical properties of commercially available films of biopolymers such as starch, pullulan, and agar were greatly influenced by temperature and moisture ; however, cellulose-starch blend films were much less influenced. This is a new characteristic achieved by blending starch with cellulose. Cellulose and cellulose-starch blend films were resistant to hot water, i.e., keeping their film forms in hot water. Moreover, disintegration of the blend films commonly seen in hot water can be controlled by blending carrageenan or sodium alginate as a third component.