Performances of starch foam improved by an alginate coating

This research aims to develop an environmentally friendly food packaging based on starch foam coated with alginate. The foam was coated with various concentrations of an alginate solution (0, 0.5, 1.0, 1.5, and 2.0 %w/v). The effects of these coatings on the properties of starch foam were then investigated. The results showed that the alginate coating increased the density of the starch foam. Starch foam coated with the alginate solution at a concentration of 1.0 %w/v showed the optimum flexural stress at maximum load (4.72 MPa), hardness (96), and mass loss in water (5.51 %). These results showed significant improvements in these properties by comparison with the uncoated foam. The alginate coating slightly improved the thermal stability of the starch foam and did not significantly delay the biodegradation of the starch foam in soil. In conclusion, coating starch foam with an alginate solution presents a viable approach to developing sustainable food packaging materials with enhanced mechanical and water resistance properties. • An alginate coating improved properties of starch foam. • A 1.0 %w/v alginate solution produced the best starch foam properties. • Mass loss in water of starch foams decreased when coated with alginate. • Alginate coating did not slow the biodegradation of the starch foam.