Oxygen-scavenging coatings and films based on lignosulfonates and laccase.
Laccase and lignosulfonates were included in coating colors and embedded in latex-based or starch-based films and coatings on foil or board. After 6 days at 23 °C and 100% relative humidity, the oxygen content in airtight chambers decreased from 1.0% (synthetic gas consisting of 99% N(2) and 1% O(2)) to 0.3% in the presence of board coated with lignosulfonate and laccase, while the oxygen content remained unchanged in control experiments without enzyme. The water stability of lignosulfonate-containing latex-based coatings and starch-based films was improved after laccase-catalyzed oxidation of lignosulfonates, which indicates polymerization to products with lower solubility in water. Furthermore, the E' modulus of starch-based films increased with 30%, which indicates laccase-catalyzed polymerization of lignosulfonates resulting in increased stiffness of the film. The results suggest that laccases and lignosulfonates can be used as an oxygen-scavenging system in active packaging and that enzyme-catalyzed polymerization of lignosulfonates contributes to improved water stability and mechanical properties.
Department of Chemical Engineering, Karlstad University, SE-651 88 Karlstad, Sweden.
Kristin
K
Johansson
Sandra
S
Winestrand
Caisa
C
Johansson
Lars
L
Järnström
Leif J
LJ
Jönsson
D001709:Biotechnology / Q000379:methods*; D018857:Food Packaging / Q000295:instrumentation* / Q000379:methods*; D042845:Laccase / Q000737:chemistry*; D007840:Latex / Q000737:chemistry; D008031:Lignin / Q000031:analogs & derivatives* / Q000737:chemistry; D010100:Oxygen / Q000032:analysis; D058105:Polymerization
D007840:Latex; C001545:lignosulfuric acid; D008031:Lignin; D042845:Laccase; D010100:Oxygen