Biodegradable food packaging trays made from cassava starch, sunflower proteins and cellulose fibers were obtained by a foam baking
process. The effect of varying the proportions of these three components on physico-chemical and mechanical properties of the trays
was studied, as was the relationship between these properties and the trays’ microstructure. All trays presented thicknesses between 1.55
and 1.76 mm, and densities between 0.46 and 0.59 g/cm3. The increment of fiber concentration from 10% to 20% w/w improved the
mechanical properties and slightly reduced the post-pressing moisture content, but increased the water absorption capacity of the material
in at least 15%. The addition of sunflower proteins till 20% w/w reduced significantly the post-pressing moisture content (ca. 5.7%),
the water absorption capacity (till 43%) and the relative deformation of the trays (till 21%). The formulation presenting the best properties
contained 20% fiber and 10% protein isolate, and had a maximal resistance of 6.57 MPa and a 38% reduction in water absorption
capacity, corresponding to a more compact, homogeneous and dense microstructure.
2007 Published by Elsevier Ltd.