Fish-Based Biopolymer Complex Coacervate Coating for Improved Paper Oxygen and Water Barrier.

Food packaging is critical to prevent food waste, but most of the packaging used today is not sustainable. Paper-based packaging materials offer a renewable option, but exhibit poor resistance to common permeants such as oxygen, grease, and water vapor. In this work, a complex coacervate coating is prepared from two waste biopolymers, gelatin and DNA, and applied to kraft paper to substantially improve its barrier properties. Thermally curing the coating after deposition decreases the water vapor transmission rate and oxygen transmission rate by 83 and 99%, respectively, relative to uncoated paper. This work represents one of the best fully biobased barrier coatings reported for paper and is a promising option for sustainable food packaging.