A cost-effective, eco-friendly, and health-promoting packaging system that prevents the passage of greases and oils would fulfill an urgent need. This review discusses what is known about the highly divergent technological paths that have been studied to achieve these objectives. Before the emergence of plastic films, the paper industry addressed these objectives in two ways, by parchmentizing and by high levels of refining of the fibers. Parchmentizing means passing the paper through a bath of concentrated sulfuric acid, followed by rinsing out the acid and drying the sheet. Though both parchmentized paper and highly refined greaseproof paper products are still made, they have been substantially displaced by oil-repellent fluorocarbon treatments of paper. The fluorocarbon treatments have allowed papermakers to achieve greaseproof properties with ordinary paper machine equipment at ordinary refining levels and without a need to immerse the paper in strong acid. Now, however, due to environmental concerns and regulations, the paper industry needs more options. Some promising directions in published research include advances in chemistry, superoleophobic surfaces, nanocellulose films, and systems to protect nanocellulose films from the effects of moisture.

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